diff --git a/components/ProfileSettings.tsx b/components/ProfileSettings.tsx
index 1d5f734..0cac415 100644
--- a/components/ProfileSettings.tsx
+++ b/components/ProfileSettings.tsx
@@ -1,10 +1,10 @@
 import { useEffect, useState } from 'react';
-import { Loader2, Check } from 'lucide-react';
+import { Loader2, Check, AlertTriangle } from 'lucide-react';
 import { Button } from './ui/button';
 import { Card, CardContent, CardHeader, CardTitle } from './ui/card';
 import { Input } from './ui/input';
 import { Label } from './ui/label';
-import { useSession } from '../lib/auth-client';
+import { useSession, signOut } from '../lib/auth-client';
 import { validatePhoneOrEmail } from '../lib/validators';
 
 export function ProfileSettings() {
@@ -17,6 +17,9 @@ export function ProfileSettings() {
   const [saving, setSaving] = useState(false);
   const [error, setError] = useState('');
   const [saved, setSaved] = useState(false);
+  const [showDeleteConfirm, setShowDeleteConfirm] = useState(false);
+  const [deleting, setDeleting] = useState(false);
+  const [deleteError, setDeleteError] = useState('');
 
   useEffect(() => {
     fetch('/api/profile', { credentials: 'include' })
@@ -172,6 +175,78 @@ export function ProfileSettings() {
         </Card>
       </form>
 
+      <Card className="mt-4 border-red-200">
+        <CardHeader>
+          <CardTitle className="text-base text-red-600 flex items-center gap-2">
+            <AlertTriangle className="w-4 h-4" /> Delete account
+          </CardTitle>
+        </CardHeader>
+        <CardContent className="pb-6">
+          {!showDeleteConfirm ? (
+            <>
+              <p className="text-sm text-muted-foreground mb-3">
+                Permanently delete your account and all associated data including
+                chemicals and protocols. This action cannot be undone.
+              </p>
+              <Button
+                variant="destructive"
+                onClick={() => setShowDeleteConfirm(true)}
+              >
+                Delete account
+              </Button>
+            </>
+          ) : (
+            <>
+              <p className="text-sm text-red-600 font-medium mb-3">
+                Are you sure? All your data will be permanently deleted.
+              </p>
+              {deleteError && (
+                <p className="text-sm text-red-600 mb-3">{deleteError}</p>
+              )}
+              <div className="flex gap-2">
+                <Button
+                  variant="destructive"
+                  disabled={deleting}
+                  onClick={async () => {
+                    setDeleting(true);
+                    setDeleteError('');
+                    try {
+                      const res = await fetch('/api/account/delete', {
+                        method: 'POST',
+                        credentials: 'include',
+                      });
+                      if (!res.ok) {
+                        const data = await res.json().catch(() => ({}));
+                        setDeleteError(data.error || 'Failed to delete account.');
+                        setDeleting(false);
+                        return;
+                      }
+                      await signOut();
+                      window.location.href = '/';
+                    } catch {
+                      setDeleteError('Failed to delete account.');
+                      setDeleting(false);
+                    }
+                  }}
+                >
+                  {deleting ? 'Deleting...' : 'Yes, delete my account'}
+                </Button>
+                <Button
+                  variant="outline"
+                  disabled={deleting}
+                  onClick={() => {
+                    setShowDeleteConfirm(false);
+                    setDeleteError('');
+                  }}
+                >
+                  Cancel
+                </Button>
+              </div>
+            </>
+          )}
+        </CardContent>
+      </Card>
+
       <p className="text-center mt-6">
         <a href="/privacy" className="text-xs text-muted-foreground hover:text-foreground transition-colors">
           Privacy Policy
diff --git a/server/src/index.ts b/server/src/index.ts
index 47853ee..f87fa50 100644
--- a/server/src/index.ts
+++ b/server/src/index.ts
@@ -7,6 +7,7 @@ import { authRateLimiter, apiRateLimiter } from './auth/rateLimiter.js';
 import chemicalsRouter from './routes/chemicals.js';
 import protocolsRouter from './routes/protocols.js';
 import profileRouter from './routes/profile.js';
+import accountRouter from './routes/account.js';
 import path from 'path';
 import { fileURLToPath } from 'url';
 
@@ -93,6 +94,7 @@ app.use('/api', apiRateLimiter);
 app.use('/api/chemicals', chemicalsRouter);
 app.use('/api/protocols', protocolsRouter);
 app.use('/api/profile', profileRouter);
+app.use('/api/account', accountRouter);
 
 app.get('/api/health', (_req, res) => res.json({ ok: true }));
 
diff --git a/server/src/routes/account.ts b/server/src/routes/account.ts
new file mode 100644
index 0000000..d4d2793
--- /dev/null
+++ b/server/src/routes/account.ts
@@ -0,0 +1,57 @@
+import { Router } from 'express';
+import { pool } from '../db/pool.js';
+import { requireAuth } from '../auth/middleware.js';
+import fs from 'fs';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const uploadsDir = process.env.UPLOADS_DIR || path.join(__dirname, '../../uploads');
+
+const router = Router();
+router.use(requireAuth);
+
+// POST /api/account/delete
+router.post('/delete', async (req, res) => {
+  const userId = req.user!.id;
+  const client = await pool.connect();
+
+  try {
+    await client.query('BEGIN');
+
+    // 1. Delete all chemicals for this user
+    await client.query('DELETE FROM chemicals WHERE user_id = $1', [userId]);
+
+    // 2. Delete all protocols for this user
+    await client.query('DELETE FROM protocols WHERE user_id = $1', [userId]);
+
+    // 3. Delete user profile (has CASCADE, but be explicit)
+    await client.query('DELETE FROM user_profile WHERE user_id = $1', [userId]);
+
+    // 4. Delete sessions and accounts (CASCADE from user, but be explicit)
+    await client.query('DELETE FROM session WHERE "userId" = $1', [userId]);
+    await client.query('DELETE FROM account WHERE "userId" = $1', [userId]);
+    await client.query('DELETE FROM verification WHERE identifier = $1', [userId]);
+
+    // 5. Delete the user record itself
+    await client.query('DELETE FROM "user" WHERE id = $1', [userId]);
+
+    await client.query('COMMIT');
+
+    // 6. Clean up uploaded files outside the transaction
+    const userUploadsDir = path.join(uploadsDir, userId);
+    if (fs.existsSync(userUploadsDir)) {
+      fs.rmSync(userUploadsDir, { recursive: true, force: true });
+    }
+
+    res.json({ deleted: true });
+  } catch (err) {
+    await client.query('ROLLBACK');
+    console.error('Account deletion failed:', err);
+    res.status(500).json({ error: 'Account deletion failed' });
+  } finally {
+    client.release();
+  }
+});
+
+export default router;