diff --git a/app/[locale]/calendar/page.tsx b/app/[locale]/calendar/page.tsx
index 0b1e2238..4f56a171 100644
--- a/app/[locale]/calendar/page.tsx
+++ b/app/[locale]/calendar/page.tsx
@@ -765,7 +765,7 @@ export default function CalendarPage() {
       return;
     }
 
-    debug.log('Calendar visibility summary', {
+    debug.log('calendar', 'Calendar visibility summary', {
       totalEvents: events.length,
       visibleEvents: visibleEvents.length,
       hiddenEvents: hiddenEvents.length,
diff --git a/app/[locale]/page.tsx b/app/[locale]/page.tsx
index 94af300d..8c047226 100644
--- a/app/[locale]/page.tsx
+++ b/app/[locale]/page.tsx
@@ -352,13 +352,13 @@ export default function Home() {
 
             if (pushEnabled) {
               setPushConnected(true);
-              debug.log('[Push] Push notifications successfully enabled');
+              debug.log('push', '[Push] Push notifications successfully enabled');
             } else {
-              debug.log('[Push] Push notifications not available on this server');
+              debug.log('push', '[Push] Push notifications not available on this server');
             }
           } catch (error) {
             // Push notifications are optional - don't break the app if they fail
-            debug.log('[Push] Failed to setup push notifications:', error);
+            debug.log('push', '[Push] Failed to setup push notifications:', error);
           }
         } catch (error) {
           console.error('Error loading email data:', error);
@@ -392,7 +392,7 @@ export default function Home() {
   useEffect(() => {
     // Clear any existing timeout when email changes
     if (markAsReadTimeoutRef.current) {
-      debug.log('[Mark as Read] Clearing previous timeout');
+      debug.log('email', '[Mark as Read] Clearing previous timeout');
       clearTimeout(markAsReadTimeoutRef.current);
       markAsReadTimeoutRef.current = null;
     }
@@ -404,20 +404,20 @@ export default function Home() {
 
     // Get current setting value
     const markAsReadDelay = useSettingsStore.getState().markAsReadDelay;
-    debug.log('[Mark as Read] Delay setting:', markAsReadDelay, 'ms for email:', selectedEmail.id);
+    debug.log('email', '[Mark as Read] Delay setting:', markAsReadDelay, 'ms for email:', selectedEmail.id);
 
     if (markAsReadDelay === -1) {
       // Never mark as read automatically
-      debug.log('[Mark as Read] Never mode - email will stay unread');
+      debug.log('email', '[Mark as Read] Never mode - email will stay unread');
     } else if (markAsReadDelay === 0) {
       // Mark as read instantly
-      debug.log('[Mark as Read] Instant mode - marking as read now');
+      debug.log('email', '[Mark as Read] Instant mode - marking as read now');
       markAsRead(client, selectedEmail.id, true);
     } else {
       // Mark as read after delay
-      debug.log('[Mark as Read] Delayed mode - will mark as read in', markAsReadDelay, 'ms');
+      debug.log('email', '[Mark as Read] Delayed mode - will mark as read in', markAsReadDelay, 'ms');
       markAsReadTimeoutRef.current = setTimeout(() => {
-        debug.log('[Mark as Read] Timeout fired - marking as read now');
+        debug.log('email', '[Mark as Read] Timeout fired - marking as read now');
         markAsRead(client, selectedEmail.id, true);
         markAsReadTimeoutRef.current = null;
       }, markAsReadDelay);
@@ -426,7 +426,7 @@ export default function Home() {
     // Cleanup on unmount or when dependencies change
     return () => {
       if (markAsReadTimeoutRef.current) {
-        debug.log('[Mark as Read] Cleanup - clearing timeout');
+        debug.log('email', '[Mark as Read] Cleanup - clearing timeout');
         clearTimeout(markAsReadTimeoutRef.current);
         markAsReadTimeoutRef.current = null;
       }
@@ -441,7 +441,7 @@ export default function Home() {
       if (emailNotificationsEnabled && emailNotificationSound) {
         playNotificationSound(notificationSoundChoice);
       }
-      debug.log('New email received:', newEmailNotification.subject);
+      debug.log('email', 'New email received:', newEmailNotification.subject);
       clearNewEmailNotification();
     }
   }, [newEmailNotification, clearNewEmailNotification]);
diff --git a/components/email/email-viewer.tsx b/components/email/email-viewer.tsx
index 68af0db0..d0e8ce5b 100644
--- a/components/email/email-viewer.tsx
+++ b/components/email/email-viewer.tsx
@@ -1820,12 +1820,12 @@ export function EmailViewer({
 
     const tnefAtt = email.attachments.find(att => isTnefAttachment(att.name, att.type));
     if (!tnefAtt?.blobId) {
-      debug.log('TNEF: No winmail.dat attachment found in email', email?.id);
+      debug.log('email', 'TNEF: No winmail.dat attachment found in email', email?.id);
       return;
     }
 
-    debug.group('TNEF Processing');
-    debug.log('Found TNEF attachment:', tnefAtt.name, 'type:', tnefAtt.type, 'blobId:', tnefAtt.blobId, 'size:', tnefAtt.size);
+    debug.group('TNEF Processing', 'email');
+    debug.log('email', 'Found TNEF attachment:', tnefAtt.name, 'type:', tnefAtt.type, 'blobId:', tnefAtt.blobId, 'size:', tnefAtt.size);
 
     // Check if the email already has a usable HTML body with real content
     // Outlook often forwards TNEF emails with an HTML body that's just Word
@@ -1835,46 +1835,46 @@ export function EmailViewer({
     let hasRealHtmlBody = !!htmlValue;
     if (hasRealHtmlBody && htmlValue && isHtmlBodyEffectivelyEmpty(htmlValue)) {
       hasRealHtmlBody = false;
-      debug.log('TNEF: Email HTML body is effectively empty (only boilerplate/whitespace), treating as no body');
+      debug.log('email', 'TNEF: Email HTML body is effectively empty (only boilerplate/whitespace), treating as no body');
     }
     if (hasRealHtmlBody) {
-      debug.log('TNEF: Email has real HTML body, will extract attachments only');
+      debug.log('email', 'TNEF: Email has real HTML body, will extract attachments only');
     } else {
-      debug.log('TNEF: Email has no usable HTML body, proceeding with full TNEF extraction');
+      debug.log('email', 'TNEF: Email has no usable HTML body, proceeding with full TNEF extraction');
     }
 
     let cancelled = false;
 
     async function processTnef() {
       try {
-        debug.time('TNEF fetch blob');
+        debug.time('TNEF fetch blob', 'email');
         const blobBytes = await client!.fetchBlobArrayBuffer(tnefAtt!.blobId!);
-        debug.timeEnd('TNEF fetch blob');
-        debug.log('TNEF: Fetched blob, size:', blobBytes.byteLength, 'bytes');
+        debug.timeEnd('TNEF fetch blob', 'email');
+        debug.log('email', 'TNEF: Fetched blob, size:', blobBytes.byteLength, 'bytes');
 
         if (cancelled) {
-          debug.log('TNEF: Processing cancelled after fetch');
+          debug.log('email', 'TNEF: Processing cancelled after fetch');
           debug.groupEnd();
           return;
         }
         if (blobBytes.byteLength === 0) {
-          debug.warn('TNEF: Fetched blob is empty (0 bytes)');
+          debug.warn('email', 'TNEF: Fetched blob is empty (0 bytes)');
           debug.groupEnd();
           return;
         }
 
         const tnefData = new Uint8Array(blobBytes);
-        debug.time('TNEF parse');
+        debug.time('TNEF parse', 'email');
         const parsed = parseTnef(tnefData);
-        debug.timeEnd('TNEF parse');
+        debug.timeEnd('TNEF parse', 'email');
 
         if (cancelled) {
-          debug.log('TNEF: Processing cancelled after parse');
+          debug.log('email', 'TNEF: Processing cancelled after parse');
           debug.groupEnd();
           return;
         }
 
-        debug.log('TNEF parse result — htmlBody:', !!parsed.htmlBody, '(' + (parsed.htmlBody?.length ?? 0) + ' chars)', ', body:', !!parsed.body, '(' + (parsed.body?.length ?? 0) + ' chars)', ', attachments:', parsed.attachments.length);
+        debug.log('email', 'TNEF parse result — htmlBody:', !!parsed.htmlBody, '(' + (parsed.htmlBody?.length ?? 0) + ' chars)', ', body:', !!parsed.body, '(' + (parsed.body?.length ?? 0) + ' chars)', ', attachments:', parsed.attachments.length);
 
         if (parsed.htmlBody && !hasRealHtmlBody) {
           setTnefHtml(parsed.htmlBody);
@@ -1884,11 +1884,11 @@ export function EmailViewer({
         }
         if (parsed.attachments.length > 0) {
           setTnefAttachments(parsed.attachments);
-          debug.log('TNEF extracted attachments:', parsed.attachments.map(a => a.name + ' (' + a.mimeType + ', ' + a.data.byteLength + ' bytes)').join(', '));
+          debug.log('email', 'TNEF extracted attachments:', parsed.attachments.map(a => a.name + ' (' + a.mimeType + ', ' + a.data.byteLength + ' bytes)').join(', '));
         }
 
         if (!parsed.htmlBody && !parsed.body && parsed.attachments.length === 0) {
-          debug.warn('TNEF: Parsing succeeded but no content was extracted — the winmail.dat may use an unsupported format');
+          debug.warn('email', 'TNEF: Parsing succeeded but no content was extracted — the winmail.dat may use an unsupported format');
         }
 
         debug.groupEnd();
@@ -1926,13 +1926,13 @@ export function EmailViewer({
     const hasRealText = !!textValue;
 
     if (hasRealHtml || hasRealText) {
-      debug.log('Embedded RFC822: Outer email has real body content, not unwrapping');
+      debug.log('email', 'Embedded RFC822: Outer email has real body content, not unwrapping');
       return;
     }
 
-    debug.group('Embedded RFC822 Unwrapping');
-    debug.log('Found message/rfc822 attachment:', rfc822Att.name, 'blobId:', rfc822Att.blobId, 'size:', rfc822Att.size);
-    debug.log('Outer email body is empty, will unwrap embedded email');
+    debug.group('Embedded RFC822 Unwrapping', 'email');
+    debug.log('email', 'Found message/rfc822 attachment:', rfc822Att.name, 'blobId:', rfc822Att.blobId, 'size:', rfc822Att.size);
+    debug.log('email', 'Outer email body is empty, will unwrap embedded email');
 
     let cancelled = false;
 
@@ -1941,7 +1941,7 @@ export function EmailViewer({
         const blobBytes = await client!.fetchBlobArrayBuffer(rfc822Att!.blobId!);
         if (cancelled) { debug.groupEnd(); return; }
         if (blobBytes.byteLength === 0) {
-          debug.warn('Embedded RFC822: Fetched blob is empty');
+          debug.warn('email', 'Embedded RFC822: Fetched blob is empty');
           debug.groupEnd();
           return;
         }
@@ -1951,7 +1951,7 @@ export function EmailViewer({
         const parsed = await parser.parse(new Uint8Array(blobBytes));
         if (cancelled) { debug.groupEnd(); return; }
 
-        debug.log('Embedded RFC822 parsed — html:', !!parsed.html, '(' + (parsed.html?.length ?? 0) + ' chars)',
+        debug.log('email', 'Embedded RFC822 parsed — html:', !!parsed.html, '(' + (parsed.html?.length ?? 0) + ' chars)',
           ', text:', !!parsed.text, '(' + (parsed.text?.length ?? 0) + ' chars)',
           ', attachments:', parsed.attachments?.length ?? 0);
 
@@ -1963,7 +1963,7 @@ export function EmailViewer({
         }
         if (parsed.attachments && parsed.attachments.length > 0) {
           setEmbeddedEmailAttachments(parsed.attachments as PostalMimeAttachment[]);
-          debug.log('Embedded RFC822 attachments:', parsed.attachments.map(
+          debug.log('email', 'Embedded RFC822 attachments:', parsed.attachments.map(
             a => (a.filename || 'unnamed') + ' (' + a.mimeType + ')'
           ).join(', '));
         }
diff --git a/components/settings/advanced-settings.tsx b/components/settings/advanced-settings.tsx
index 0dd634c8..aad81b22 100644
--- a/components/settings/advanced-settings.tsx
+++ b/components/settings/advanced-settings.tsx
@@ -7,11 +7,12 @@ import { useConfig } from '@/hooks/use-config';
 import { SettingsSection, SettingItem, ToggleSwitch } from './settings-section';
 import { Button } from '@/components/ui/button';
 import { usePolicyStore } from '@/stores/policy-store';
+import { ALL_DEBUG_CATEGORIES } from '@/stores/settings-store';
 
 export function AdvancedSettings() {
   const t = useTranslations('settings.advanced');
   const tCommon = useTranslations('common');
-  const { debugMode, senderFavicons, settingsSyncDisabled, updateSetting, resetToDefaults, exportSettings, importSettings } =
+  const { debugMode, debugCategories, senderFavicons, settingsSyncDisabled, updateSetting, resetToDefaults, exportSettings, importSettings } =
     useSettingsStore();
   const { settingsSyncEnabled } = useConfig();
   const [showResetConfirm, setShowResetConfirm] = useState(false);
@@ -72,6 +73,30 @@ export function AdvancedSettings() {
       </SettingItem>
       )}
 
+      {/* Debug Categories */}
+      {debugMode && !isSettingHidden('debugMode') && isFeatureEnabled('debugModeEnabled') && (
+        <div className="ml-4 border-l-2 border-muted pl-4 space-y-1">
+          <p className="text-xs text-muted-foreground mb-2">{t('debug_categories.description')}</p>
+          {ALL_DEBUG_CATEGORIES.map((cat) => (
+            <SettingItem
+              key={cat.id}
+              label={t(`debug_categories.${cat.labelKey}`)}
+              description={t(`debug_categories.${cat.labelKey}_description`)}
+            >
+              <ToggleSwitch
+                checked={debugCategories?.[cat.id] !== false}
+                onChange={(checked) => {
+                  updateSetting('debugCategories', {
+                    ...debugCategories,
+                    [cat.id]: checked,
+                  });
+                }}
+              />
+            </SettingItem>
+          ))}
+        </div>
+      )}
+
       {/* Settings Sync */}
       {settingsSyncEnabled && (
         <SettingItem label={t('settings_sync.label')} description={t('settings_sync.description')}>
diff --git a/lib/debug.ts b/lib/debug.ts
index 4846b97f..116235b2 100644
--- a/lib/debug.ts
+++ b/lib/debug.ts
@@ -1,25 +1,53 @@
 import { useSettingsStore } from '@/stores/settings-store';
+import type { DebugCategory } from '@/stores/settings-store';
 
 /**
- * Debug logger that respects the debugMode setting.
+ * Check if debug logging is enabled, optionally for a specific category.
+ * When a category is provided, both debugMode AND that category must be enabled.
+ */
+function isEnabled(category?: DebugCategory): boolean {
+  const state = useSettingsStore.getState();
+  if (!state.debugMode) return false;
+  if (!category) return true;
+  return state.debugCategories?.[category] !== false;
+}
+
+/**
+ * Debug logger that respects the debugMode setting and category filters.
  * Use this instead of console.log for conditional debug output.
+ *
+ * Each method accepts an optional category as the first argument.
+ * When a category is provided, the message only logs if that category is enabled
+ * in Settings > Advanced > Debug Categories.
+ *
+ * Usage:
+ *   debug.log('calendar', 'Event created', event);  // Only logs when 'calendar' category is on
+ *   debug.log('Uncategorized message');               // Logs whenever debugMode is on
  */
 export const debug = {
   /**
-   * Log a debug message (only when debugMode is enabled)
+   * Log a debug message (only when debugMode is enabled and category is active)
    */
-  log: (...args: unknown[]) => {
-    if (useSettingsStore.getState().debugMode) {
-      console.log('[DEBUG]', ...args);
+  log: (categoryOrMsg: DebugCategory | unknown, ...args: unknown[]) => {
+    if (typeof categoryOrMsg === 'string' && isCategoryKey(categoryOrMsg)) {
+      if (isEnabled(categoryOrMsg)) {
+        console.log(`[DEBUG:${categoryOrMsg}]`, ...args);
+      }
+    } else if (isEnabled()) {
+      console.log('[DEBUG]', categoryOrMsg, ...args);
     }
   },
 
   /**
-   * Log a warning message (only when debugMode is enabled)
+   * Log a warning message (only when debugMode is enabled and category is active)
    */
-  warn: (...args: unknown[]) => {
-    if (useSettingsStore.getState().debugMode) {
-      console.warn('[DEBUG]', ...args);
+  warn: (categoryOrMsg: DebugCategory | unknown, ...args: unknown[]) => {
+    if (typeof categoryOrMsg === 'string' && isCategoryKey(categoryOrMsg)) {
+      if (isEnabled(categoryOrMsg)) {
+        console.warn(`[DEBUG:${categoryOrMsg}]`, ...args);
+      }
+    } else if (isEnabled()) {
+      console.warn('[DEBUG]', categoryOrMsg, ...args);
     }
   },
 
@@ -31,11 +59,11 @@ export const debug = {
   },
 
   /**
-   * Start a collapsed console group (only when debugMode is enabled)
+   * Start a collapsed console group (only when debugMode is enabled and category is active)
    */
-  group: (label: string) => {
-    if (useSettingsStore.getState().debugMode) {
-      console.group(`[DEBUG] ${label}`);
+  group: (label: string, category?: DebugCategory) => {
+    if (isEnabled(category)) {
+      console.group(`[DEBUG${category ? ':' + category : ''}] ${label}`);
     }
   },
 
@@ -43,35 +71,40 @@ export const debug = {
    * End a console group (only when debugMode is enabled)
    */
   groupEnd: () => {
-    if (useSettingsStore.getState().debugMode) {
+    if (isEnabled()) {
       console.groupEnd();
     }
   },
 
   /**
-   * Start a performance timer (only when debugMode is enabled)
+   * Start a performance timer (only when debugMode is enabled and category is active)
    */
-  time: (label: string) => {
-    if (useSettingsStore.getState().debugMode) {
-      console.time(`[DEBUG] ${label}`);
+  time: (label: string, category?: DebugCategory) => {
+    if (isEnabled(category)) {
+      console.time(`[DEBUG${category ? ':' + category : ''}] ${label}`);
     }
   },
 
   /**
    * End a performance timer (only when debugMode is enabled)
    */
-  timeEnd: (label: string) => {
-    if (useSettingsStore.getState().debugMode) {
-      console.timeEnd(`[DEBUG] ${label}`);
+  timeEnd: (label: string, category?: DebugCategory) => {
+    if (isEnabled(category)) {
+      console.timeEnd(`[DEBUG${category ? ':' + category : ''}] ${label}`);
     }
   },
 
   /**
-   * Log a table (only when debugMode is enabled)
+   * Log a table (only when debugMode is enabled and category is active)
    */
-  table: (data: unknown) => {
-    if (useSettingsStore.getState().debugMode) {
+  table: (data: unknown, category?: DebugCategory) => {
+    if (isEnabled(category)) {
       console.table(data);
     }
   }
 };
+
+const CATEGORY_KEYS = new Set<string>(['jmap', 'calendar', 'tasks', 'auth', 'filters', 'email', 'push']);
+function isCategoryKey(value: string): value is DebugCategory {
+  return CATEGORY_KEYS.has(value);
+}
diff --git a/lib/jmap/client.ts b/lib/jmap/client.ts
index c1a0a0d5..db2c6868 100644
--- a/lib/jmap/client.ts
+++ b/lib/jmap/client.ts
@@ -670,12 +670,12 @@ export class JMAPClient implements IJMAPClient {
       if (response.methodResponses?.[0]?.[0] === "Mailbox/get") {
         const rawMailboxes = (response.methodResponses[0][1].list || []) as JMAPMailbox[];
 
-        debug.log(`[JMAP Mailbox] getMailboxes returned ${rawMailboxes.length} mailboxes for account ${this.accountId}`);
+        debug.log('jmap', `[JMAP Mailbox] getMailboxes returned ${rawMailboxes.length} mailboxes for account ${this.accountId}`);
 
         // Warn if response might be truncated
         const maxObjects = this.getMaxObjectsInGet();
         if (rawMailboxes.length >= maxObjects) {
-          debug.warn(
+          debug.warn('jmap', 
             `[JMAP Mailbox] Response contains ${rawMailboxes.length} mailboxes which equals maxObjectsInGet (${maxObjects}). ` +
             `Some mailboxes may be missing — nested folders could appear orphaned at root level.`
           );
@@ -685,7 +685,7 @@ export class JMAPClient implements IJMAPClient {
         const returnedIds = new Set(rawMailboxes.map(mb => mb.id));
         const missingParents = rawMailboxes.filter(mb => mb.parentId && !returnedIds.has(mb.parentId));
         if (missingParents.length > 0) {
-          debug.warn(
+          debug.warn('jmap', 
             `[JMAP Mailbox] ${missingParents.length} mailbox(es) reference parentId not in response (will be orphaned):`,
             missingParents.map(mb => ({ id: mb.id, name: mb.name, parentId: mb.parentId }))
           );
@@ -755,12 +755,12 @@ export class JMAPClient implements IJMAPClient {
           if (response.methodResponses?.[0]?.[0] === "Mailbox/get") {
             const rawMailboxes = (response.methodResponses[0][1].list || []) as JMAPMailbox[];
 
-            debug.log(`[JMAP Mailbox] getAllMailboxes: account ${accountId} returned ${rawMailboxes.length} mailboxes (isPrimary: ${isPrimary})`);
+            debug.log('jmap', `[JMAP Mailbox] getAllMailboxes: account ${accountId} returned ${rawMailboxes.length} mailboxes (isPrimary: ${isPrimary})`);
 
             // Warn if response might be truncated
             const maxObjects = this.getMaxObjectsInGet();
             if (rawMailboxes.length >= maxObjects) {
-              debug.warn(
+              debug.warn('jmap', 
                 `[JMAP Mailbox] Account ${accountId}: response contains ${rawMailboxes.length} mailboxes which equals maxObjectsInGet (${maxObjects}). ` +
                 `Some mailboxes may be missing.`
               );
@@ -1995,7 +1995,7 @@ export class JMAPClient implements IJMAPClient {
     lines.push('END:VCALENDAR');
     const icsContent = lines.join('\r\n') + '\r\n';
 
-    debug.log('[iMIP] Generated ICS:\n' + icsContent);
+    debug.log('calendar', '[iMIP] Generated ICS:\n' + icsContent);
 
     const statusLabels: Record<string, string> = {
       ACCEPTED: 'Accepted',
@@ -2005,7 +2005,7 @@ export class JMAPClient implements IJMAPClient {
     const statusLabel = statusLabels[opts.status] || opts.status;
     const subject = `${statusLabel}: ${opts.summary || 'Event'}`;
 
-    debug.log('[iMIP] identityId:', finalIdentityId);
+    debug.log('calendar', '[iMIP] identityId:', finalIdentityId);
 
     const emailId = `imip-reply-${Date.now()}`;
     const emailCreate: Record<string, unknown> = {
@@ -2038,12 +2038,12 @@ export class JMAPClient implements IJMAPClient {
       }, "1"],
     ];
 
-    debug.log('[iMIP] Sending JMAP request with', methodCalls.length, 'method calls');
-    debug.log('[iMIP] Email create payload:', JSON.stringify(emailCreate, null, 2));
+    debug.log('calendar', '[iMIP] Sending JMAP request with', methodCalls.length, 'method calls');
+    debug.log('calendar', '[iMIP] Email create payload:', JSON.stringify(emailCreate, null, 2));
 
     const response = await this.request(methodCalls);
 
-    debug.log('[iMIP] JMAP response:', JSON.stringify(response.methodResponses, null, 2));
+    debug.log('calendar', '[iMIP] JMAP response:', JSON.stringify(response.methodResponses, null, 2));
 
     if (response.methodResponses) {
       for (const [methodName, result] of response.methodResponses) {
@@ -2058,7 +2058,7 @@ export class JMAPClient implements IJMAPClient {
         }
       }
     }
-    debug.log('[iMIP] sendImipReply completed successfully');
+    debug.log('calendar', '[iMIP] sendImipReply completed successfully');
   }
 
   /**
@@ -2222,7 +2222,7 @@ export class JMAPClient implements IJMAPClient {
   async sendImipCancellation(event: CalendarEvent): Promise<void> {
     if (!event.participants) return;
     if (event.status && event.status !== 'cancelled') {
-      debug.warn('sendImipCancellation called on non-cancelled event, status:', event.status);
+      debug.warn('calendar', 'sendImipCancellation called on non-cancelled event, status:', event.status);
     }
 
     const mailboxes = await this.getMailboxes();
@@ -3361,8 +3361,8 @@ export class JMAPClient implements IJMAPClient {
     const { originalId: _oi, originalCalendarIds: _oc, accountId: _ai, accountName: _an, isShared: _is, ...cleanEvent } = event as CalendarEvent;
     cleanRecurrenceRules(cleanEvent as unknown as Record<string, unknown>);
 
-    debug.group('CalendarEvent/create');
-    debug.log('CalendarEvent/create outgoing payload', {
+    debug.group('CalendarEvent/create', 'calendar');
+    debug.log('calendar', 'CalendarEvent/create outgoing payload', {
       accountId,
       sendSchedulingMessages,
       eventKeys: Object.keys(cleanEvent),
@@ -3382,40 +3382,40 @@ export class JMAPClient implements IJMAPClient {
       ["CalendarEvent/set", setArgs, "0"]
     ], this.calendarUsing());
 
-    debug.log('CalendarEvent/create raw set response', response.methodResponses?.[0]?.[1] || null);
+    debug.log('calendar', 'CalendarEvent/create raw set response', response.methodResponses?.[0]?.[1] || null);
 
     if (response.methodResponses?.[0]?.[0] === "CalendarEvent/set") {
       const result = response.methodResponses[0][1];
 
       if (result.notCreated?.["new-event"]) {
         const error = result.notCreated["new-event"];
-        debug.warn('CalendarEvent/create notCreated', error);
-        debug.warn('CalendarEvent/create invalid properties', error.properties);
-        debug.warn('CalendarEvent/create sent keys', Object.keys(cleanEvent));
+        debug.warn('calendar', 'CalendarEvent/create notCreated', error);
+        debug.warn('calendar', 'CalendarEvent/create invalid properties', error.properties);
+        debug.warn('calendar', 'CalendarEvent/create sent keys', Object.keys(cleanEvent));
         debug.groupEnd();
         throw new Error(error.description || "Failed to create calendar event");
       }
 
       const createdId = result.created?.["new-event"]?.id;
-      debug.log('CalendarEvent/create server acknowledged created id', {
+      debug.log('calendar', 'CalendarEvent/create server acknowledged created id', {
         createdId,
         created: result.created?.['new-event'] || null,
       });
 
       if (createdId) {
         const created = await this.getCalendarEvent(createdId, targetAccountId);
-        debug.log('CalendarEvent/create fetched created event', getCalendarEventDebugSnapshot(created));
+        debug.log('calendar', 'CalendarEvent/create fetched created event', getCalendarEventDebugSnapshot(created));
 
         if (created?.uid) {
           try {
             const verificationMatches = await this.queryCalendarEvents({ uid: created.uid }, undefined, undefined, targetAccountId);
-            debug.log('CalendarEvent/create verification query by uid', {
+            debug.log('calendar', 'CalendarEvent/create verification query by uid', {
               uid: created.uid,
               matchCount: verificationMatches.length,
               matches: verificationMatches.map((match) => getCalendarEventDebugSnapshot(match)),
             });
           } catch (verificationError) {
-            debug.warn('CalendarEvent/create verification query failed', verificationError);
+            debug.warn('calendar', 'CalendarEvent/create verification query failed', verificationError);
           }
         }
 
@@ -3424,7 +3424,7 @@ export class JMAPClient implements IJMAPClient {
           return created;
         }
 
-        debug.warn('CalendarEvent/create server returned created id but CalendarEvent/get returned null', {
+        debug.warn('calendar', 'CalendarEvent/create server returned created id but CalendarEvent/get returned null', {
           createdId,
           targetAccountId,
         });
@@ -3455,7 +3455,7 @@ export class JMAPClient implements IJMAPClient {
       createMap[`new-${i}`] = clean;
     }
 
-    debug.log('CalendarEvent/batchCreate', { count: events.length, accountId });
+    debug.log('calendar', 'CalendarEvent/batchCreate', { count: events.length, accountId });
 
     const response = await this.request([
       ["CalendarEvent/set", { accountId, create: createMap }, "0"]
@@ -3471,7 +3471,7 @@ export class JMAPClient implements IJMAPClient {
         if (result.created?.[key]?.id) {
           createdIds.push(result.created[key].id);
         } else if (result.notCreated?.[key]) {
-          debug.warn(`CalendarEvent/batchCreate failed for ${key}`, result.notCreated[key]);
+          debug.warn('calendar', `CalendarEvent/batchCreate failed for ${key}`, result.notCreated[key]);
           failed.push(key);
         }
       }
@@ -3496,7 +3496,7 @@ export class JMAPClient implements IJMAPClient {
       createdEvents = list.map((e: CalendarEvent) => normalizeCalendarEventLike(e));
     }
 
-    debug.log('CalendarEvent/batchCreate result', {
+    debug.log('calendar', 'CalendarEvent/batchCreate result', {
       requested: events.length,
       created: createdEvents.length,
       failed: failed.length,
@@ -3527,7 +3527,7 @@ export class JMAPClient implements IJMAPClient {
       setArgs.sendSchedulingMessages = sendSchedulingMessages;
     }
 
-    debug.log('CalendarEvent/set update request', { eventId, accountId, cleanUpdateKeys: Object.keys(cleanUpdates), sendSchedulingMessages });
+    debug.log('calendar', 'CalendarEvent/set update request', { eventId, accountId, cleanUpdateKeys: Object.keys(cleanUpdates), sendSchedulingMessages });
 
     const response = await this.request([
       ["CalendarEvent/set", setArgs, "0"]
@@ -3549,7 +3549,7 @@ export class JMAPClient implements IJMAPClient {
         debug.error('CalendarEvent/set notUpdated', { eventId, error });
         throw new Error(error.description || "Failed to update calendar event");
       }
-      debug.log('CalendarEvent/set update success', { eventId, updated: result.updated ? Object.keys(result.updated) : null });
+      debug.log('calendar', 'CalendarEvent/set update success', { eventId, updated: result.updated ? Object.keys(result.updated) : null });
       return;
     }
 
@@ -3600,7 +3600,7 @@ export class JMAPClient implements IJMAPClient {
       setArgs.sendSchedulingMessages = sendSchedulingMessages;
     }
 
-    debug.log('CalendarEvent/set destroy request', { eventId, accountId, sendSchedulingMessages });
+    debug.log('calendar', 'CalendarEvent/set destroy request', { eventId, accountId, sendSchedulingMessages });
 
     const response = await this.request([
       ["CalendarEvent/set", setArgs, "0"]
@@ -3622,7 +3622,7 @@ export class JMAPClient implements IJMAPClient {
         debug.error('CalendarEvent/set notDestroyed', { eventId, error });
         throw new Error(error.description || "Failed to delete calendar event");
       }
-      debug.log('CalendarEvent/set destroy success', { eventId, destroyed: result.destroyed });
+      debug.log('calendar', 'CalendarEvent/set destroy success', { eventId, destroyed: result.destroyed });
       return;
     }
 
@@ -3654,8 +3654,8 @@ export class JMAPClient implements IJMAPClient {
 
   async getCalendarTasks(calendarIds?: string[], targetAccountId?: string): Promise<CalendarTask[]> {
     const accountId = targetAccountId || this.getCalendarsAccountId();
-    debug.group('CalendarTask/fetch');
-    debug.log('CalendarTask/fetch start', { accountId, calendarIds: calendarIds || 'all' });
+    debug.group('CalendarTask/fetch', 'tasks');
+    debug.log('tasks', 'CalendarTask/fetch start', { accountId, calendarIds: calendarIds || 'all' });
 
     try {
       // Strategy 1: query with types filter (JMAP spec compliant)
@@ -3664,7 +3664,7 @@ export class JMAPClient implements IJMAPClient {
         filter.inCalendars = calendarIds;
       }
 
-      debug.log('CalendarTask/fetch query filter', filter);
+      debug.log('tasks', 'CalendarTask/fetch query filter', filter);
 
       const response = await this.request([
         ["CalendarEvent/query", { accountId, filter, limit: 1000 }, "0"],
@@ -3678,13 +3678,13 @@ export class JMAPClient implements IJMAPClient {
       const queryResponse = response.methodResponses?.[0];
       const getResponse = response.methodResponses?.[1];
 
-      debug.log('CalendarTask/fetch query method', queryResponse?.[0]);
-      debug.log('CalendarTask/fetch query result', queryResponse?.[1]);
+      debug.log('tasks', 'CalendarTask/fetch query method', queryResponse?.[0]);
+      debug.log('tasks', 'CalendarTask/fetch query result', queryResponse?.[1]);
 
       if (queryResponse?.[0] === "error") {
-        debug.warn('CalendarTask/fetch types filter not supported, falling back to full scan', queryResponse[1]);
+        debug.warn('tasks', 'CalendarTask/fetch types filter not supported, falling back to full scan', queryResponse[1]);
         const tasks = await this.getCalendarTasksFallback(calendarIds, targetAccountId);
-        debug.log('CalendarTask/fetch fallback returned', tasks.length, 'tasks');
+        debug.log('tasks', 'CalendarTask/fetch fallback returned', tasks.length, 'tasks');
         debug.groupEnd();
         return tasks;
       }
@@ -3692,22 +3692,22 @@ export class JMAPClient implements IJMAPClient {
       if (getResponse?.[0] === "CalendarEvent/get") {
         const list = (getResponse[1].list || []) as CalendarTask[];
         const queryIds = queryResponse?.[1]?.ids || [];
-        debug.log('CalendarTask/fetch query returned', queryIds.length, 'ids:', queryIds);
-        debug.log('CalendarTask/fetch get returned', list.length, 'objects');
+        debug.log('calendar', 'CalendarTask/fetch query returned', queryIds.length, 'ids:', queryIds);
+        debug.log('calendar', 'CalendarTask/fetch get returned', list.length, 'objects');
 
         // If the types filter returned 0 results, the server may have silently
         // ignored it (e.g. Stalwart with CalDAV-created VTODOs). Fall back to
         // a full scan so we can detect tasks by their properties.
         if (queryIds.length === 0) {
-          debug.warn('CalendarTask/fetch types filter returned 0 results, falling back to full scan');
+          debug.warn('tasks', 'CalendarTask/fetch types filter returned 0 results, falling back to full scan');
           const tasks = await this.getCalendarTasksFallback(calendarIds, targetAccountId);
-          debug.log('CalendarTask/fetch fallback returned', tasks.length, 'tasks');
+          debug.log('tasks', 'CalendarTask/fetch fallback returned', tasks.length, 'tasks');
           debug.groupEnd();
           return tasks;
         }
 
         list.forEach((task, i) => {
-          debug.log(`CalendarTask/fetch [${i}]`, {
+          debug.log('tasks', `CalendarTask/fetch [${i}]`, {
             id: task.id,
             uid: task.uid,
             '@type': task['@type'],
@@ -3724,12 +3724,12 @@ export class JMAPClient implements IJMAPClient {
           ...task,
           '@type': 'Task' as const,
         }));
-        debug.log('CalendarTask/fetch complete,', results.length, 'tasks');
+        debug.log('tasks', 'CalendarTask/fetch complete,', results.length, 'tasks');
         debug.groupEnd();
         return results;
       }
 
-      debug.warn('CalendarTask/fetch unexpected response shape', response.methodResponses);
+      debug.warn('tasks', 'CalendarTask/fetch unexpected response shape', response.methodResponses);
       debug.groupEnd();
       return [];
     } catch (error) {
@@ -3746,7 +3746,7 @@ export class JMAPClient implements IJMAPClient {
    */
   private async getCalendarTasksFallback(calendarIds?: string[], targetAccountId?: string): Promise<CalendarTask[]> {
     const accountId = targetAccountId || this.getCalendarsAccountId();
-    debug.log('CalendarTask/fallback using CalendarEvent/get ids:null to fetch all objects');
+    debug.log('calendar', 'CalendarTask/fallback using CalendarEvent/get ids:null to fetch all objects');
 
     // CalendarEvent/get with ids:null returns ALL calendar objects regardless of @type
     const response = await this.request([
@@ -3758,12 +3758,12 @@ export class JMAPClient implements IJMAPClient {
     ], this.calendarUsing());
 
     if (response.methodResponses?.[0]?.[0] !== "CalendarEvent/get") {
-      debug.warn('CalendarTask/fallback unexpected response', response.methodResponses?.[0]);
+      debug.warn('calendar', 'CalendarTask/fallback unexpected response', response.methodResponses?.[0]);
       return [];
     }
 
     const allObjects = (response.methodResponses[0][1].list || []) as Record<string, unknown>[];
-    debug.log('CalendarTask/fallback total calendar objects returned:', allObjects.length);
+    debug.log('tasks', 'CalendarTask/fallback total calendar objects returned:', allObjects.length);
 
     const tasks: CalendarTask[] = [];
     const calendarIdSet = calendarIds ? new Set(calendarIds) : null;
@@ -3779,7 +3779,7 @@ export class JMAPClient implements IJMAPClient {
         || ('percentComplete' in obj);
       const isCalDavTask = type !== 'Event' && hasTaskFields;
 
-      debug.log('CalendarTask/fallback scan', {
+      debug.log('tasks', 'CalendarTask/fallback scan', {
         id: obj.id,
         '@type': type,
         title: obj.title,
@@ -3796,7 +3796,7 @@ export class JMAPClient implements IJMAPClient {
       if (calendarIdSet) {
         const objCalendarIds = obj.calendarIds as Record<string, boolean> | undefined;
         if (objCalendarIds && !Object.keys(objCalendarIds).some(id => calendarIdSet.has(id))) {
-          debug.log('CalendarTask/fallback skipping task (not in requested calendars)', obj.id);
+          debug.log('tasks', 'CalendarTask/fallback skipping task (not in requested calendars)', obj.id);
           return;
         }
       }
@@ -3804,9 +3804,9 @@ export class JMAPClient implements IJMAPClient {
       tasks.push({ ...obj, '@type': 'Task' as const } as CalendarTask);
     });
 
-    debug.log('CalendarTask/fallback detected', tasks.length, 'tasks');
+    debug.log('tasks', 'CalendarTask/fallback detected', tasks.length, 'tasks');
     tasks.forEach((t, i) => {
-      debug.log(`CalendarTask/fallback [${i}]`, {
+      debug.log('tasks', `CalendarTask/fallback [${i}]`, {
         id: t.id,
         uid: t.uid,
         title: t.title,
@@ -3825,9 +3825,9 @@ export class JMAPClient implements IJMAPClient {
     const { '@type': _type, ...taskData } = task;
     const cleanTask = { ...taskData, '@type': 'Task' };
 
-    debug.group('CalendarTask/create');
-    debug.log('CalendarTask/create accountId', accountId);
-    debug.log('CalendarTask/create outgoing payload', cleanTask);
+    debug.group('CalendarTask/create', 'tasks');
+    debug.log('tasks', 'CalendarTask/create accountId', accountId);
+    debug.log('tasks', 'CalendarTask/create outgoing payload', cleanTask);
 
     const response = await this.request([
       ["CalendarEvent/set", {
@@ -3838,27 +3838,27 @@ export class JMAPClient implements IJMAPClient {
     ], this.calendarUsing());
 
     const result = response.methodResponses?.[0]?.[1];
-    debug.log('CalendarTask/create raw set response', result);
+    debug.log('tasks', 'CalendarTask/create raw set response', result);
 
     if (result?.notCreated?.["new-task"]) {
       const error = result.notCreated["new-task"];
-      debug.warn('CalendarTask/create REJECTED by server', error);
+      debug.warn('tasks', 'CalendarTask/create REJECTED by server', error);
       debug.groupEnd();
       throw new Error(error.description || "Failed to create task");
     }
 
     const createdId = result?.created?.["new-task"]?.id;
     const serverCreated = result?.created?.["new-task"];
-    debug.log('CalendarTask/create server acknowledged', { createdId, serverCreated });
+    debug.log('tasks', 'CalendarTask/create server acknowledged', { createdId, serverCreated });
 
     if (!createdId) {
-      debug.warn('CalendarTask/create no id in server response');
+      debug.warn('tasks', 'CalendarTask/create no id in server response');
       debug.groupEnd();
       throw new Error("Failed to create task — no id returned");
     }
 
     // Fetch back with task-specific properties
-    debug.log('CalendarTask/create re-fetching with task properties', { createdId, properties: [...CALENDAR_TASK_PROPERTIES] });
+    debug.log('calendar', 'CalendarTask/create re-fetching with task properties', { createdId, properties: [...CALENDAR_TASK_PROPERTIES] });
     const getResponse = await this.request([
       ["CalendarEvent/get", {
         accountId,
@@ -3870,10 +3870,10 @@ export class JMAPClient implements IJMAPClient {
     if (getResponse.methodResponses?.[0]?.[0] === "CalendarEvent/get") {
       const list = getResponse.methodResponses[0][1].list || [];
       const notFound = getResponse.methodResponses[0][1].notFound || [];
-      debug.log('CalendarTask/create get response', { found: list.length, notFound });
+      debug.log('calendar', 'CalendarTask/create get response', { found: list.length, notFound });
       if (list[0]) {
         const created = { ...list[0], '@type': 'Task' as const } as CalendarTask;
-        debug.log('CalendarTask/create final task object', {
+        debug.log('tasks', 'CalendarTask/create final task object', {
           id: created.id,
           uid: created.uid,
           '@type': created['@type'],
@@ -3889,7 +3889,7 @@ export class JMAPClient implements IJMAPClient {
       }
     }
 
-    debug.warn('CalendarTask/create re-fetch returned nothing for id', createdId);
+    debug.warn('tasks', 'CalendarTask/create re-fetch returned nothing for id', createdId);
     debug.groupEnd();
     throw new Error("Failed to fetch created task");
   }
diff --git a/lib/notification-sound.ts b/lib/notification-sound.ts
index 02d87de8..13a21a34 100644
--- a/lib/notification-sound.ts
+++ b/lib/notification-sound.ts
@@ -31,7 +31,7 @@ function playFile(file: string) {
   const audio = new Audio(file);
   audio.volume = 0.3;
   audio.play().catch((e) => {
-    debug.log('Could not play audio file, falling back to beep:', e);
+    debug.log('push', 'Could not play audio file, falling back to beep:', e);
     playBeep();
   });
 }
@@ -47,6 +47,6 @@ export function playNotificationSound(sound?: NotificationSoundChoice) {
       playBeep();
     }
   } catch (e) {
-    debug.log('Could not play notification sound:', e);
+    debug.log('push', 'Could not play notification sound:', e);
   }
 }
diff --git a/lib/sieve/generator.ts b/lib/sieve/generator.ts
index ad705e30..6a494c2d 100644
--- a/lib/sieve/generator.ts
+++ b/lib/sieve/generator.ts
@@ -147,7 +147,7 @@ export function generateScript(rules: FilterRule[], vacation?: VacationSieveConf
 
   for (const rule of enabledRules) {
     if (rule.conditions.length === 0 || rule.actions.length === 0) {
-      debug.warn(`Skipping rule "${rule.name}": empty conditions or actions`);
+      debug.warn('filters', `Skipping rule "${rule.name}": empty conditions or actions`);
       continue;
     }
 
diff --git a/lib/sieve/parser.ts b/lib/sieve/parser.ts
index 381510c3..a2533809 100644
--- a/lib/sieve/parser.ts
+++ b/lib/sieve/parser.ts
@@ -109,7 +109,7 @@ export function parseScript(content: string): ParseResult {
   try {
     metadata = JSON.parse(jsonStr);
   } catch (e) {
-    debug.warn('Failed to parse Sieve metadata JSON:', e);
+    debug.warn('filters', 'Failed to parse Sieve metadata JSON:', e);
     return OPAQUE;
   }
 
diff --git a/lib/tnef.ts b/lib/tnef.ts
index 42200e3f..2d679e30 100644
--- a/lib/tnef.ts
+++ b/lib/tnef.ts
@@ -236,11 +236,11 @@ export function parseTnef(data: Uint8Array): TnefResult {
     attachments: [],
   };
 
-  debug.group('TNEF Parser');
-  debug.log('Input data size:', data.byteLength, 'bytes');
+  debug.group('TNEF Parser', 'email');
+  debug.log('email', 'Input data size:', data.byteLength, 'bytes');
 
   if (data.byteLength < 6) {
-    debug.warn('TNEF data too small (< 6 bytes), skipping');
+    debug.warn('email', 'TNEF data too small (< 6 bytes), skipping');
     debug.groupEnd();
     return result;
   }
@@ -249,11 +249,11 @@ export function parseTnef(data: Uint8Array): TnefResult {
 
   const signature = r.readUint32LE();
   if (signature !== TNEF_SIGNATURE) {
-    debug.warn('Invalid TNEF signature:', '0x' + signature.toString(16).toUpperCase(), '(expected 0x223E9F78)');
+    debug.warn('email', 'Invalid TNEF signature:', '0x' + signature.toString(16).toUpperCase(), '(expected 0x223E9F78)');
     debug.groupEnd();
     return result;
   }
-  debug.log('TNEF signature valid');
+  debug.log('email', 'TNEF signature valid');
 
   r.skip(2); // legacy key
 
@@ -268,7 +268,7 @@ export function parseTnef(data: Uint8Array): TnefResult {
     attrCount++;
 
     if (attrLen > r.remaining - 2) {
-      debug.warn('Attribute #' + attrCount + ': truncated data — need', attrLen, 'bytes but only', r.remaining - 2, 'available');
+      debug.warn('email', 'Attribute #' + attrCount + ': truncated data — need', attrLen, 'bytes but only', r.remaining - 2, 'available');
       break;
     }
 
@@ -276,17 +276,17 @@ export function parseTnef(data: Uint8Array): TnefResult {
     r.skip(2); // checksum
 
     const levelName = level === LVL_MESSAGE ? 'MESSAGE' : level === LVL_ATTACHMENT ? 'ATTACHMENT' : 'UNKNOWN(' + level + ')';
-    debug.log('Attribute #' + attrCount + ':', levelName, 'id=0x' + attrID.toString(16).toUpperCase(), 'len=' + attrLen);
+    debug.log('email', 'Attribute #' + attrCount + ':', levelName, 'id=0x' + attrID.toString(16).toUpperCase(), 'len=' + attrLen);
 
     if (level === LVL_MESSAGE) {
       if (attrID === attBody) {
         result.body = new TextDecoder('utf-8').decode(attrData);
-        debug.log('  → Extracted plain text body (' + result.body.length + ' chars)');
+        debug.log('email', '  → Extracted plain text body (' + result.body.length + ' chars)');
       } else if (attrID === attMAPIProps) {
         const props = parseMAPIProps(attrData);
-        debug.log('  → Parsed', props.size, 'MAPI properties from message');
+        debug.log('email', '  → Parsed', props.size, 'MAPI properties from message');
         props.forEach((val, propID) => {
-          debug.log('    MAPI prop 0x' + propID.toString(16).toUpperCase(), 'type=0x' + val.type.toString(16), 'value=' + (val.value instanceof Uint8Array ? val.value.byteLength + ' bytes' : val.value));
+          debug.log('email', '    MAPI prop 0x' + propID.toString(16).toUpperCase(), 'type=0x' + val.type.toString(16), 'value=' + (val.value instanceof Uint8Array ? val.value.byteLength + ' bytes' : val.value));
         });
 
         // HTML body
@@ -298,9 +298,9 @@ export function parseTnef(data: Uint8Array): TnefResult {
           } else {
             result.htmlBody = new TextDecoder('utf-8').decode(htmlProp.value);
           }
-          debug.log('  → Extracted HTML body (' + result.htmlBody.length + ' chars)');
+          debug.log('email', '  → Extracted HTML body (' + result.htmlBody.length + ' chars)');
         } else {
-          debug.log('  → No HTML body property (PR_BODY_HTML 0x1013) found in MAPI props');
+          debug.log('email', '  → No HTML body property (PR_BODY_HTML 0x1013) found in MAPI props');
         }
 
         // Plain text body from MAPI props (fallback)
@@ -308,9 +308,9 @@ export function parseTnef(data: Uint8Array): TnefResult {
           const bodyProp = props.get(PR_BODY);
           if (bodyProp?.value instanceof Uint8Array) {
             result.body = decodeMAPIString(bodyProp.value, bodyProp.type & 0x0FFF);
-            debug.log('  → Extracted plain text body from MAPI props (' + result.body.length + ' chars)');
+            debug.log('email', '  → Extracted plain text body from MAPI props (' + result.body.length + ' chars)');
           } else {
-            debug.log('  → No plain text body property (PR_BODY 0x1000) found in MAPI props');
+            debug.log('email', '  → No plain text body property (PR_BODY 0x1000) found in MAPI props');
           }
         }
       }
@@ -318,7 +318,7 @@ export function parseTnef(data: Uint8Array): TnefResult {
       if (attrID === attAttachRenddata) {
         // Start of a new attachment — flush previous
         if (curAttach?.data) {
-          debug.log('  → Flushing previous attachment:', curAttach.name, '(' + curAttach.mimeType + ',', curAttach.data.byteLength, 'bytes)');
+          debug.log('email', '  → Flushing previous attachment:', curAttach.name, '(' + curAttach.mimeType + ',', curAttach.data.byteLength, 'bytes)');
           result.attachments.push({
             name: curAttach.name,
             mimeType: curAttach.mimeType,
@@ -326,40 +326,40 @@ export function parseTnef(data: Uint8Array): TnefResult {
           });
         }
         curAttach = { name: 'attachment', mimeType: 'application/octet-stream', data: null };
-        debug.log('  → New attachment started');
+        debug.log('email', '  → New attachment started');
       } else if (attrID === attAttachTitle && curAttach) {
         let len = attrData.byteLength;
         if (len > 0 && attrData[len - 1] === 0) len--;
         curAttach.name = new TextDecoder('utf-8').decode(attrData.subarray(0, len));
-        debug.log('  → Attachment short name:', curAttach.name);
+        debug.log('email', '  → Attachment short name:', curAttach.name);
       } else if (attrID === attAttachData && curAttach) {
         curAttach.data = attrData;
-        debug.log('  → Attachment data (attAttachData):', attrData.byteLength, 'bytes');
+        debug.log('email', '  → Attachment data (attAttachData):', attrData.byteLength, 'bytes');
       } else if (attrID === attAttachment && curAttach) {
         const props = parseMAPIProps(attrData);
-        debug.log('  → Parsed', props.size, 'MAPI properties from attachment');
+        debug.log('email', '  → Parsed', props.size, 'MAPI properties from attachment');
         props.forEach((val, propID) => {
-          debug.log('    MAPI prop 0x' + propID.toString(16).toUpperCase(), 'type=0x' + val.type.toString(16), 'value=' + (val.value instanceof Uint8Array ? val.value.byteLength + ' bytes' : val.value));
+          debug.log('email', '    MAPI prop 0x' + propID.toString(16).toUpperCase(), 'type=0x' + val.type.toString(16), 'value=' + (val.value instanceof Uint8Array ? val.value.byteLength + ' bytes' : val.value));
         });
 
         const longName = props.get(PR_ATTACH_LONG_FILENAME);
         if (longName?.value instanceof Uint8Array) {
           curAttach.name = decodeMAPIString(longName.value, longName.type & 0x0FFF);
-          debug.log('  → Attachment long filename:', curAttach.name);
+          debug.log('email', '  → Attachment long filename:', curAttach.name);
         }
 
         const mimeTag = props.get(PR_ATTACH_MIME_TAG);
         if (mimeTag?.value instanceof Uint8Array) {
           curAttach.mimeType = decodeMAPIString(mimeTag.value, mimeTag.type & 0x0FFF);
-          debug.log('  → Attachment MIME type:', curAttach.mimeType);
+          debug.log('email', '  → Attachment MIME type:', curAttach.mimeType);
         }
 
         const attachData = props.get(PR_ATTACH_DATA_BIN);
         if (attachData?.value instanceof Uint8Array) {
           curAttach.data = attachData.value;
-          debug.log('  → Attachment data (PR_ATTACH_DATA_BIN):', attachData.value.byteLength, 'bytes');
+          debug.log('email', '  → Attachment data (PR_ATTACH_DATA_BIN):', attachData.value.byteLength, 'bytes');
         } else {
-          debug.log('  → No PR_ATTACH_DATA_BIN found in attachment MAPI props');
+          debug.log('email', '  → No PR_ATTACH_DATA_BIN found in attachment MAPI props');
         }
       }
     }
@@ -367,7 +367,7 @@ export function parseTnef(data: Uint8Array): TnefResult {
 
   // Flush last attachment
   if (curAttach?.data) {
-    debug.log('Flushing final attachment:', curAttach.name, '(' + curAttach.mimeType + ',', curAttach.data.byteLength, 'bytes)');
+    debug.log('email', 'Flushing final attachment:', curAttach.name, '(' + curAttach.mimeType + ',', curAttach.data.byteLength, 'bytes)');
     result.attachments.push({
       name: curAttach.name,
       mimeType: curAttach.mimeType,
@@ -375,9 +375,9 @@ export function parseTnef(data: Uint8Array): TnefResult {
     });
   }
 
-  debug.log('TNEF parsing complete — body:', !!result.body, ', htmlBody:', !!result.htmlBody, ', attachments:', result.attachments.length);
+  debug.log('email', 'TNEF parsing complete — body:', !!result.body, ', htmlBody:', !!result.htmlBody, ', attachments:', result.attachments.length);
   if (result.attachments.length > 0) {
-    debug.table(result.attachments.map(a => ({ name: a.name, mimeType: a.mimeType, size: a.data.byteLength })));
+    debug.table(result.attachments.map(a => ({ name: a.name, mimeType: a.mimeType, size: a.data.byteLength })), 'email');
   }
   debug.groupEnd();
 
diff --git a/lib/utils.ts b/lib/utils.ts
index 47f59d2a..f6130fd4 100644
--- a/lib/utils.ts
+++ b/lib/utils.ts
@@ -152,8 +152,7 @@ function deduplicateMailboxes(mailboxes: Mailbox[]): Mailbox[] {
       removed.push({ id: mb.id, name: mb.name, matchedRole: matchedRole!.name, parentId: mb.parentId });
       // Warn if this removed mailbox is a parent of other mailboxes (orphan risk)
       if (referencedParentIds.has(mb.id)) {
-        debug.warn(
-          `[Mailbox Tree] Deduplication removed mailbox "${mb.name}" (id: ${mb.id}) which is a parent of other mailboxes. ` +
+        debug.warn('jmap', `[Mailbox Tree] Deduplication removed mailbox "${mb.name}" (id: ${mb.id}) which is a parent of other mailboxes. ` +
           `Matched role mailbox: "${matchedRole!.name}" (role: ${matchedRole!.role}). ` +
           `Children referencing parentId "${mb.id}" will be orphaned to root level.`
         );
@@ -162,7 +161,7 @@ function deduplicateMailboxes(mailboxes: Mailbox[]): Mailbox[] {
   });
 
   if (removed.length > 0) {
-    debug.log(`[Mailbox Tree] Deduplication removed ${removed.length} mailbox(es):`, removed);
+    debug.log('jmap', `[Mailbox Tree] Deduplication removed ${removed.length} mailbox(es):`, removed);
   }
 
   return result;
@@ -170,13 +169,13 @@ function deduplicateMailboxes(mailboxes: Mailbox[]): Mailbox[] {
 
 // Build a hierarchical tree structure from flat mailbox array
 export function buildMailboxTree(mailboxes: Mailbox[]): MailboxNode[] {
-  debug.log(`[Mailbox Tree] Building tree from ${mailboxes.length} mailboxes`);
+  debug.log('jmap', `[Mailbox Tree] Building tree from ${mailboxes.length} mailboxes`);
 
   // Deduplicate mailboxes first
   const deduplicated = deduplicateMailboxes(mailboxes);
 
   if (deduplicated.length !== mailboxes.length) {
-    debug.log(`[Mailbox Tree] After deduplication: ${deduplicated.length} mailboxes (removed ${mailboxes.length - deduplicated.length})`);
+    debug.log('jmap', `[Mailbox Tree] After deduplication: ${deduplicated.length} mailboxes (removed ${mailboxes.length - deduplicated.length})`);
   }
 
   // Separate own and shared mailboxes
@@ -223,8 +222,7 @@ export function buildMailboxTree(mailboxes: Mailbox[]): MailboxNode[] {
   });
 
   if (orphanedMailboxes.length > 0) {
-    debug.warn(
-      `[Mailbox Tree] ${orphanedMailboxes.length} orphaned mailbox(es) moved to root level (missing parent):`,
+    debug.warn('jmap', `[Mailbox Tree] ${orphanedMailboxes.length} orphaned mailbox(es) moved to root level (missing parent):`,
       orphanedMailboxes
     );
   }
@@ -241,8 +239,7 @@ export function buildMailboxTree(mailboxes: Mailbox[]): MailboxNode[] {
     }
     return max;
   };
-  debug.log(
-    `[Mailbox Tree] Built tree: ${rootMailboxes.length} root nodes, ` +
+  debug.log('jmap', `[Mailbox Tree] Built tree: ${rootMailboxes.length} root nodes, ` +
     `max depth: ${maxDepth(rootMailboxes)}, ` +
     `total own: ${ownMailboxes.length}, shared: ${sharedMailboxes.length}`
   );
diff --git a/locales/en/common.json b/locales/en/common.json
index ea2d03b4..82403163 100644
--- a/locales/en/common.json
+++ b/locales/en/common.json
@@ -1164,6 +1164,23 @@
         "label": "Debug Mode",
         "description": "Enable detailed logging for troubleshooting"
       },
+      "debug_categories": {
+        "description": "Select which categories to log. Disable categories you don't need to reduce console noise.",
+        "jmap": "JMAP Client",
+        "jmap_description": "Mailbox operations, email fetching, and JMAP protocol requests",
+        "calendar": "Calendar",
+        "calendar_description": "Calendar events, imports, and scheduling messages",
+        "tasks": "Tasks",
+        "tasks_description": "Calendar task creation, fetching, and updates",
+        "auth": "Authentication",
+        "auth_description": "Login, TOTP, token exchange, and session management",
+        "filters": "Filters",
+        "filters_description": "Sieve filter rules and vacation scripts",
+        "email": "Email Viewing",
+        "email_description": "Email rendering, TNEF processing, and mark-as-read",
+        "push": "Push Notifications",
+        "push_description": "Push notification setup and delivery"
+      },
       "settings_sync": {
         "label": "Settings Sync",
         "description": "Sync your settings across browsers and devices"
diff --git a/stores/auth-store.ts b/stores/auth-store.ts
index 4b9de063..8cafb9ca 100644
--- a/stores/auth-store.ts
+++ b/stores/auth-store.ts
@@ -393,13 +393,13 @@ export const useAuthStore = create<AuthState>()(
                 oauthAccessToken = access_token;
                 oauthExpiresIn = expires_in;
                 upgradedToOAuth = true;
-                debug.log('TOTP login upgraded to token-based auth (has_refresh_token=' + has_refresh_token + ')');
+                debug.log('auth', 'TOTP login upgraded to token-based auth (has_refresh_token=' + has_refresh_token + ')');
               } else {
                 const errorBody = await tokenRes.json().catch(() => ({ error: 'unknown' }));
-                debug.warn('TOTP token exchange failed:', tokenRes.status, errorBody);
+                debug.warn('auth', 'TOTP token exchange failed:', tokenRes.status, errorBody);
               }
             } catch (err) {
-              debug.warn('TOTP token exchange error:', err);
+              debug.warn('auth', 'TOTP token exchange error:', err);
             }
 
             // If token exchange failed, enable TOTP re-auth prompt so the
@@ -407,7 +407,7 @@ export const useAuthStore = create<AuthState>()(
             if (!upgradedToOAuth) {
               const { useTotpReauthStore } = await import('@/stores/totp-reauth-store');
               client.enableTotpReauth(password, () => useTotpReauthStore.getState().requestTotp());
-              debug.log('TOTP re-auth enabled — user will be prompted for fresh codes on session expiry');
+              debug.log('auth', 'TOTP re-auth enabled — user will be prompted for fresh codes on session expiry');
             }
           }
 
diff --git a/stores/calendar-store.ts b/stores/calendar-store.ts
index 27168f89..58f592f1 100644
--- a/stores/calendar-store.ts
+++ b/stores/calendar-store.ts
@@ -197,7 +197,7 @@ export const useCalendarStore = create<CalendarStore>()(
           // Expand recurring events client-side (Stalwart doesn't support
           // mutations on synthetic IDs from server-side expandRecurrences)
           const events = expandRecurringEvents(validEvents, start, end);
-          debug.log('Calendar fetchEvents completed', {
+          debug.log('calendar', 'Calendar fetchEvents completed', {
             start,
             end,
             rawCount: rawEvents.length,
@@ -206,7 +206,7 @@ export const useCalendarStore = create<CalendarStore>()(
             droppedEvents,
           });
           if (droppedEvents > 0) {
-            debug.warn('Calendar fetchEvents dropped malformed events without a start field', { droppedEvents });
+            debug.warn('calendar', 'Calendar fetchEvents dropped malformed events without a start field', { droppedEvents });
           }
           set({ events, isLoadingEvents: false, dateRange: { start, end } });
         } catch (error) {
@@ -237,7 +237,7 @@ export const useCalendarStore = create<CalendarStore>()(
           if (event.originalCalendarIds) {
             cleanEvent.calendarIds = event.originalCalendarIds;
           }
-          debug.log('Calendar createEvent request', {
+          debug.log('calendar', 'Calendar createEvent request', {
             event: getStoreEventDebugSnapshot(cleanEvent),
             sendSchedulingMessages,
             targetAccountId,
@@ -256,7 +256,7 @@ export const useCalendarStore = create<CalendarStore>()(
             ? mappedCreated.start >= currentDateRange.start && mappedCreated.start <= currentDateRange.end
             : null;
 
-          debug.log('Calendar createEvent response', {
+          debug.log('calendar', 'Calendar createEvent response', {
             created: getStoreEventDebugSnapshot(created),
             mappedCreated: getStoreEventDebugSnapshot(mappedCreated),
             isVisible,
@@ -265,21 +265,21 @@ export const useCalendarStore = create<CalendarStore>()(
           });
 
           if (!isVisible) {
-            debug.warn('Created event is hidden by current calendar filters', {
+            debug.warn('calendar', 'Created event is hidden by current calendar filters', {
               selectedCalendarIds,
               createdCalendarIds,
             });
           }
 
           if (inCurrentDateRange === false) {
-            debug.warn('Created event is outside the currently loaded date range', {
+            debug.warn('calendar', 'Created event is outside the currently loaded date range', {
               currentDateRange,
               createdStart: mappedCreated.start,
             });
           }
 
           if (mappedCreated.showWithoutTime && mappedCreated.timeZone !== null) {
-            debug.warn('Created all-day event came back with a non-null timeZone', {
+            debug.warn('calendar', 'Created all-day event came back with a non-null timeZone', {
               timeZone: mappedCreated.timeZone,
               event: getStoreEventDebugSnapshot(mappedCreated),
             });
@@ -301,7 +301,7 @@ export const useCalendarStore = create<CalendarStore>()(
           const storeEvent = get().events.find(e => e.id === id);
           const realId = storeEvent?.originalId || id;
           const targetAccountId = storeEvent?.accountId;
-          debug.log('Calendar updateEvent', {
+          debug.log('calendar', 'Calendar updateEvent', {
             storeId: id,
             realId,
             uid: storeEvent?.uid,
@@ -445,20 +445,20 @@ export const useCalendarStore = create<CalendarStore>()(
               await client.updateCalendarEvent(eventId, { calendarIds } as Partial<CalendarEvent>, undefined, targetAccountId);
               linked++;
             } catch (err) {
-              debug.warn(`Import: failed to link event ${eventId} to target calendar:`, err);
+              debug.warn('calendar', `Import: failed to link event ${eventId} to target calendar:`, err);
             }
           }
 
           if (linked > 0) {
-            debug.log(`Import: linked ${linked} existing events to target calendar`);
+            debug.log('calendar', `Import: linked ${linked} existing events to target calendar`);
           }
           const skipped = eventsToProcess.length - newEvents.length - eventsToLink.length;
           if (skipped > 0) {
-            debug.log(`Import: skipped ${skipped} events already in target calendar`);
+            debug.log('calendar', `Import: skipped ${skipped} events already in target calendar`);
           }
           eventsToProcess = newEvents;
         } catch (error) {
-          debug.warn('Could not fetch existing events for deduplication, proceeding without:', error);
+          debug.warn('calendar', 'Could not fetch existing events for deduplication, proceeding without:', error);
         }
 
         // Prepare all events for batch creation
@@ -543,7 +543,7 @@ export const useCalendarStore = create<CalendarStore>()(
             const { created, failed } = await client.batchCreateCalendarEvents(batch, targetAccountId);
             imported += created.length;
             if (failed.length > 0) {
-              debug.warn(`Import batch ${i / BATCH_SIZE + 1}: ${failed.length} events failed`);
+              debug.warn('calendar', `Import batch ${i / BATCH_SIZE + 1}: ${failed.length} events failed`);
             }
           } catch (error) {
             debug.error(`Import batch ${i / BATCH_SIZE + 1} failed:`, error);
@@ -577,7 +577,7 @@ export const useCalendarStore = create<CalendarStore>()(
               debug.error('Failed to send cancellation emails:', e);
             }
           }
-          debug.log('Calendar deleteEvent', {
+          debug.log('calendar', 'Calendar deleteEvent', {
             storeId: id,
             realId,
             uid: storeEvent?.uid,
@@ -675,7 +675,7 @@ export const useCalendarStore = create<CalendarStore>()(
 
             // If we couldn't destroy any events, stop to avoid infinite loop
             if (destroyed.length === 0) {
-              debug.warn('Could not delete any events, stopping clear loop. Not destroyed:', ids.length);
+              debug.warn('calendar', 'Could not delete any events, stopping clear loop. Not destroyed:', ids.length);
               break;
             }
 
@@ -744,7 +744,7 @@ export const useCalendarStore = create<CalendarStore>()(
             await get().refreshICalSubscription(client, subscription.id);
           } catch {
             // Subscription created, initial fetch failed - user can retry
-            debug.warn('Initial subscription fetch failed for:', name);
+            debug.warn('calendar', 'Initial subscription fetch failed for:', name);
           }
 
           return subscription;
@@ -892,7 +892,7 @@ export const useCalendarStore = create<CalendarStore>()(
             try {
               await get().refreshICalSubscription(client, sub.id);
             } catch {
-              debug.warn('Failed to refresh subscription:', sub.name);
+              debug.warn('calendar', 'Failed to refresh subscription:', sub.name);
             }
           }
         }
diff --git a/stores/filter-store.ts b/stores/filter-store.ts
index eced8d15..ef828356 100644
--- a/stores/filter-store.ts
+++ b/stores/filter-store.ts
@@ -53,7 +53,7 @@ export const useFilterStore = create<FilterStore>()((set, get) => ({
       set({ sieveCapabilities: capabilities });
 
       const allScripts = await client.getSieveScripts();
-      debug.log('Sieve scripts fetched:', allScripts.length);
+      debug.log('filters', 'Sieve scripts fetched:', allScripts.length);
 
       // Skip the server-managed 'vacation' script (RFC 9661 §4) — it can only
       // be modified via VacationResponse/set, not SieveScript/set.
@@ -73,10 +73,10 @@ export const useFilterStore = create<FilterStore>()((set, get) => ({
       const result = parseScript(content);
 
       if (result.isOpaque) {
-        debug.log('Sieve script is opaque (hand-edited)');
+        debug.log('filters', 'Sieve script is opaque (hand-edited)');
         set({ isLoading: false, isOpaque: true, rules: [], vacationSettings: result.vacation || null });
       } else {
-        debug.log('Parsed', result.rules.length, 'filter rules');
+        debug.log('filters', 'Parsed', result.rules.length, 'filter rules');
         set({ isLoading: false, isOpaque: false, rules: result.rules, vacationSettings: result.vacation || null });
       }
     } catch (error) {
@@ -108,7 +108,7 @@ export const useFilterStore = create<FilterStore>()((set, get) => ({
       }
 
       set({ isSaving: false, rawScript: content });
-      debug.log('Filters saved successfully');
+      debug.log('filters', 'Filters saved successfully');
     } catch (error) {
       debug.error('Failed to save filters:', error);
       set({
@@ -212,7 +212,7 @@ export const useFilterStore = create<FilterStore>()((set, get) => ({
         });
       }
 
-      debug.log('Vacation synced to sieve script');
+      debug.log('filters', 'Vacation synced to sieve script');
     } catch (error) {
       debug.error('Failed to sync vacation to sieve script:', error);
     }
diff --git a/stores/settings-store.ts b/stores/settings-store.ts
index 8af5efd4..ed981d7c 100644
--- a/stores/settings-store.ts
+++ b/stores/settings-store.ts
@@ -49,6 +49,18 @@ export const ALL_HOVER_ACTIONS: { id: HoverAction; labelKey: string }[] = [
   { id: 'spam', labelKey: 'spam' },
 ];
 
+export type DebugCategory = 'jmap' | 'calendar' | 'tasks' | 'auth' | 'filters' | 'email' | 'push';
+
+export const ALL_DEBUG_CATEGORIES: { id: DebugCategory; labelKey: string }[] = [
+  { id: 'jmap', labelKey: 'jmap' },
+  { id: 'calendar', labelKey: 'calendar' },
+  { id: 'tasks', labelKey: 'tasks' },
+  { id: 'auth', labelKey: 'auth' },
+  { id: 'filters', labelKey: 'filters' },
+  { id: 'email', labelKey: 'email' },
+  { id: 'push', labelKey: 'push' },
+];
+
 export interface KeywordDefinition {
   id: string;     // Used as JMAP keyword suffix: $label:<id>
   label: string;  // Display name
@@ -175,6 +187,7 @@ interface SettingsState {
 
   // Advanced
   debugMode: boolean;
+  debugCategories: Record<DebugCategory, boolean>;
   settingsSyncDisabled: boolean;
 
   // Actions
@@ -299,6 +312,15 @@ const DEFAULT_SETTINGS = {
 
   // Advanced
   debugMode: false,
+  debugCategories: {
+    jmap: true,
+    calendar: true,
+    tasks: true,
+    auth: true,
+    filters: true,
+    email: true,
+    push: true,
+  } as Record<DebugCategory, boolean>,
   settingsSyncDisabled: false,
 };
 
@@ -383,6 +405,7 @@ export const useSettingsStore = create<SettingsState>()(
           sidebarApps: state.sidebarApps,
           keepAppsLoaded: state.keepAppsLoaded,
           debugMode: state.debugMode,
+          debugCategories: state.debugCategories,
           settingsSyncDisabled: state.settingsSyncDisabled,
           // Cross-store settings
           theme: useThemeStore.getState().theme,
diff --git a/stores/task-store.ts b/stores/task-store.ts
index 5382282a..a2f7d070 100644
--- a/stores/task-store.ts
+++ b/stores/task-store.ts
@@ -37,13 +37,13 @@ export const useTaskStore = create<TaskStore>((set, get) => ({
   setShowCompleted: (show) => set({ showCompleted: show }),
 
   fetchTasks: async (client, calendarIds) => {
-    debug.log('TaskStore/fetchTasks start', { calendarIds: calendarIds || 'all' });
+    debug.log('tasks', 'TaskStore/fetchTasks start', { calendarIds: calendarIds || 'all' });
     set({ isLoading: true, error: null });
     try {
       const tasks = await client.getCalendarTasks(calendarIds);
-      debug.log('TaskStore/fetchTasks received', tasks.length, 'tasks');
+      debug.log('tasks', 'TaskStore/fetchTasks received', tasks.length, 'tasks');
       tasks.forEach((t, i) => {
-        debug.log(`TaskStore/fetchTasks [${i}]`, {
+        debug.log('tasks', `TaskStore/fetchTasks [${i}]`, {
           id: t.id, uid: t.uid, '@type': t['@type'],
           title: t.title, due: t.due, progress: t.progress,
           showWithoutTime: t.showWithoutTime, calendarIds: t.calendarIds,
@@ -57,9 +57,9 @@ export const useTaskStore = create<TaskStore>((set, get) => ({
   },
 
   createTask: async (client, task) => {
-    debug.log('TaskStore/createTask', task);
+    debug.log('tasks', 'TaskStore/createTask', task);
     const created = await client.createCalendarTask(task);
-    debug.log('TaskStore/createTask result', { id: created.id, uid: created.uid, title: created.title });
+    debug.log('tasks', 'TaskStore/createTask result', { id: created.id, uid: created.uid, title: created.title });
     set({ tasks: [...get().tasks, created] });
     return created;
   },