diff --git a/backend/notifications/api/serializers.py b/backend/notifications/api/serializers.py
index 0dc477d2..5048c523 100644
--- a/backend/notifications/api/serializers.py
+++ b/backend/notifications/api/serializers.py
@@ -174,6 +174,7 @@ class SubscribePushRequestSerializer(serializers.Serializer):
 
 class UnsubscribePushRequestSerializer(serializers.Serializer):
     endpoint = serializers.CharField(required=False)
+    device_group_id = serializers.UUIDField(required=False)
 
 
 class InstallationHeartbeatRequestSerializer(serializers.Serializer):
diff --git a/backend/notifications/api/views.py b/backend/notifications/api/views.py
index f0406145..ddb782a0 100644
--- a/backend/notifications/api/views.py
+++ b/backend/notifications/api/views.py
@@ -924,7 +924,10 @@ def subscribe_push(request):
             'user': request.user,
             'p256dh': keys.get('p256dh', ''),
             'auth': keys.get('auth', ''),
-            'browser': device_name,
+            # django-push-notifications keeps a legacy browser code in a
+            # varchar(10).  The human-readable device name belongs to
+            # NotificationInstallation.device_name and may be much longer.
+            'browser': _web_push_browser(request),
             'active': True,
         }
     )
@@ -1181,7 +1184,10 @@ def unsubscribe_push(request):
     """Отписка от Web Push уведомлений"""
     from push_notifications.models import WebPushDevice
 
-    endpoint = request.data.get('endpoint')
+    serializer = UnsubscribePushRequestSerializer(data=request.data)
+    serializer.is_valid(raise_exception=True)
+    endpoint = serializer.validated_data.get('endpoint')
+    device_group_id = serializer.validated_data.get('device_group_id')
 
     if endpoint:
         NotificationInstallation.objects.filter(
@@ -1196,6 +1202,29 @@ def unsubscribe_push(request):
             user=request.user,
             registration_id=endpoint
         ).delete()
+    elif device_group_id:
+        # Logout is scoped to the current physical device.  A user may still
+        # have active subscriptions on a phone, another browser, or a PWA.
+        installations = NotificationInstallation.objects.filter(
+            user=request.user,
+            device_group_id=device_group_id,
+        )
+        endpoints = list(
+            installations.exclude(endpoint__isnull=True).values_list(
+                'endpoint',
+                flat=True,
+            )
+        )
+        deleted_count, _ = WebPushDevice.objects.filter(
+            user=request.user,
+            registration_id__in=endpoints,
+        ).delete()
+        installations.update(
+            endpoint=None,
+            push_device_id=None,
+            active=False,
+            last_seen_at=timezone.now(),
+        )
     else:
         # Удалить все устройства пользователя
         deleted_count, _ = WebPushDevice.objects.filter(
@@ -1219,3 +1248,17 @@ def unsubscribe_push(request):
         'message': f'Deleted {deleted_count} push subscription(s)',
         'deleted_count': deleted_count
     })
+
+
+def _web_push_browser(request):
+    """Return a value accepted by WebPushDevice.browser (max length 10)."""
+    user_agent = request.META.get('HTTP_USER_AGENT', '').lower()
+    if 'firefox' in user_agent:
+        return 'FIREFOX'
+    if 'edg/' in user_agent or 'edge/' in user_agent:
+        return 'EDGE'
+    if 'opr/' in user_agent or 'opera' in user_agent:
+        return 'OPERA'
+    # The library has no Safari choice.  For modern HTTPS endpoints this
+    # legacy field is not used to construct the delivery URL.
+    return 'CHROME'
diff --git a/backend/tests/api/v1/notifications/test_notifications_api.py b/backend/tests/api/v1/notifications/test_notifications_api.py
index 9e862cba..24283b69 100644
--- a/backend/tests/api/v1/notifications/test_notifications_api.py
+++ b/backend/tests/api/v1/notifications/test_notifications_api.py
@@ -628,9 +628,92 @@ class TestNotificationPreferencesApi:
 
         assert response.status_code == 200
         installation = NotificationInstallation.objects.get(user=user)
+        device = WebPushDevice.objects.get(pk=installation.push_device_id)
         assert installation.app_kind == "messenger"
+        assert installation.device_name == "Safari iPhone"
         assert installation.installed is True
         assert installation.push_ready is True
+        assert device.browser == "CHROME"
+
+    def test_subscribe_push_normalizes_browser_from_user_agent(
+        self, api_client, user_factory
+    ):
+        user = user_factory()
+        api_client.force_authenticate(user=user)
+
+        response = api_client.post(
+            "/api/v1/notifications/push/subscribe/",
+            {
+                "endpoint": "https://push.example.test/long-device-name",
+                "keys": {"p256dh": "test-p256dh", "auth": "test-auth"},
+                "device_name": "Linux x86_64 · Desktop",
+            },
+            format="json",
+            HTTP_USER_AGENT="Mozilla/5.0 Firefox/142.0",
+        )
+
+        assert response.status_code == 200
+        device = WebPushDevice.objects.get(user=user)
+        installation = NotificationInstallation.objects.get(user=user)
+        assert device.browser == "FIREFOX"
+        assert installation.device_name == "Linux x86_64 · Desktop"
+
+    def test_unsubscribe_device_group_does_not_remove_other_device(
+        self, api_client, user_factory
+    ):
+        user = user_factory()
+        api_client.force_authenticate(user=user)
+        current_group = "084127c8-ac7a-47c8-92c5-d7d41713b150"
+        other_group = "73d2d87f-2cd7-44ca-a658-d7d41713a898"
+        current_device = WebPushDevice.objects.create(
+            user=user,
+            registration_id="https://push.example.test/current-device",
+            p256dh="test-p256dh",
+            auth="test-auth",
+            browser="CHROME",
+            active=True,
+        )
+        other_device = WebPushDevice.objects.create(
+            user=user,
+            registration_id="https://push.example.test/other-device",
+            p256dh="test-p256dh",
+            auth="test-auth",
+            browser="CHROME",
+            active=True,
+        )
+        current_installation = NotificationInstallation.objects.create(
+            user=user,
+            device_group_id=current_group,
+            app_kind="main",
+            endpoint=current_device.registration_id,
+            push_device_id=current_device.id,
+            installed=True,
+        )
+        other_installation = NotificationInstallation.objects.create(
+            user=user,
+            device_group_id=other_group,
+            app_kind="main",
+            endpoint=other_device.registration_id,
+            push_device_id=other_device.id,
+            installed=True,
+        )
+
+        response = api_client.delete(
+            "/api/v1/notifications/push/unsubscribe/",
+            {"device_group_id": current_group},
+            format="json",
+        )
+
+        assert response.status_code == 200
+        assert response.data["deleted_count"] == 1
+        current_installation.refresh_from_db()
+        other_installation.refresh_from_db()
+        assert current_installation.active is False
+        assert current_installation.endpoint is None
+        assert current_installation.push_device_id is None
+        assert other_installation.active is True
+        assert other_installation.endpoint == other_device.registration_id
+        assert WebPushDevice.objects.filter(pk=other_device.pk).exists()
 
     def test_delivery_routing_requires_ready_messenger(
         self, api_client, user_factory
diff --git a/frontend/src/contexts/UserContext.tsx b/frontend/src/contexts/UserContext.tsx
index 15261bdf..d08f9b29 100644
--- a/frontend/src/contexts/UserContext.tsx
+++ b/frontend/src/contexts/UserContext.tsx
@@ -11,6 +11,8 @@ import {
 } from "@/lib/api/client";
 import type { User } from "@/types/api";
 import { useRouter } from "next/navigation";
+import { unsubscribeAllLocalPushSubscriptions } from "@/lib/push";
+import { getDeviceGroupId } from "@/lib/notifications/installations";
 
 export type AuthStatus = 'loading' | 'authenticated' | 'recovering' | 'unauthenticated';
 
@@ -21,7 +23,7 @@ interface UserContextType {
     error: string | null;
     refreshUser: () => Promise<void>;
     retryAuthentication: () => Promise<void>;
-    logout: () => void;
+    logout: () => Promise<void>;
 }
 
 const UserContext = createContext<UserContextType | undefined>(undefined);
@@ -111,12 +113,26 @@ export function UserProvider({ children }: { children: ReactNode }) {
         await loadUser();
     }, [loadUser]);
 
-    const logout = useCallback(() => {
+    const logout = useCallback(async () => {
         clearRetryTimer();
-        apiClient.clearToken('logout');
-        setUser(null);
-        setStatus('unauthenticated');
-        router.replace('/login');
+        try {
+            const cleanupResults = await Promise.allSettled([
+                apiClient.unsubscribePushForDeviceGroup(getDeviceGroupId()),
+                unsubscribeAllLocalPushSubscriptions(),
+            ]);
+            cleanupResults.forEach((result) => {
+                if (result.status === 'rejected') {
+                    console.warn('[logout] Не удалось полностью очистить push-подписку:', result.reason);
+                }
+            });
+        } catch (caught) {
+            console.warn('[logout] Не удалось запустить очистку push-подписки:', caught);
+        } finally {
+            apiClient.clearToken('logout');
+            setUser(null);
+            setStatus('unauthenticated');
+            router.replace('/login');
+        }
     }, [clearRetryTimer, router]);
 
     useEffect(() => {
@@ -134,6 +150,9 @@ export function UserProvider({ children }: { children: ReactNode }) {
         const handleAuthEvent = (event: Event) => {
             const detail = (event as CustomEvent<AuthSessionEventDetail>).detail;
             if (detail?.type === 'session-cleared') {
+                void unsubscribeAllLocalPushSubscriptions().catch((caught) => {
+                    console.warn('[auth] Не удалось удалить локальную push-подписку:', caught);
+                });
                 clearRetryTimer();
                 setUser(null);
                 setStatus('unauthenticated');
diff --git a/frontend/src/lib/api/notifications.ts b/frontend/src/lib/api/notifications.ts
index 28a3eb11..e3051cf2 100644
--- a/frontend/src/lib/api/notifications.ts
+++ b/frontend/src/lib/api/notifications.ts
@@ -69,6 +69,12 @@ export function createNotificationsApi(request: RequestFn) {
             request('/api/v1/notifications/push/subscribe/', { method: 'POST', body: JSON.stringify(data) }),
         unsubscribePush: (endpoint?: string): Promise<{ status: string; message: string }> =>
             request('/api/v1/notifications/push/unsubscribe/', { method: 'DELETE', body: JSON.stringify({ endpoint }) }),
+        unsubscribePushForDeviceGroup: (deviceGroupId: string): Promise<{ status: string; message: string }> =>
+            request('/api/v1/notifications/push/unsubscribe/', {
+                method: 'DELETE',
+                body: JSON.stringify({ device_group_id: deviceGroupId }),
+                timeoutMs: 5_000,
+            }),
         heartbeatNotificationInstallation: (data: {
             installation_id: string;
             device_group_id: string;
diff --git a/frontend/src/lib/push.ts b/frontend/src/lib/push.ts
index ebcc85c8..84afba78 100644
--- a/frontend/src/lib/push.ts
+++ b/frontend/src/lib/push.ts
@@ -123,6 +123,39 @@ export async function unsubscribeFromPush(
     return success;
 }
 
+/**
+ * Remove every Web Push subscription owned by this origin in the browser.
+ * This is intentionally local-only so it can also run after an auth session
+ * expires and the API can no longer authenticate the user.
+ */
+export async function unsubscribeAllLocalPushSubscriptions(): Promise<number> {
+    if (typeof navigator === 'undefined' || !('serviceWorker' in navigator)) {
+        return 0;
+    }
+
+    const registrations = await navigator.serviceWorker.getRegistrations();
+    const shownNotifications = await Promise.all(
+        registrations.map((registration) =>
+            registration.getNotifications().catch(() => []),
+        ),
+    );
+    shownNotifications.flat().forEach((notification) => notification.close());
+
+    const subscriptions = await Promise.all(
+        registrations.map((registration) => registration.pushManager.getSubscription()),
+    );
+    const activeSubscriptions = subscriptions.filter(
+        (subscription): subscription is PushSubscription => subscription !== null,
+    );
+    const results = await Promise.allSettled(
+        activeSubscriptions.map((subscription) => subscription.unsubscribe()),
+    );
+
+    return results.filter(
+        (result) => result.status === 'fulfilled' && result.value,
+    ).length;
+}
+
 /**
  * Получает текущую push подписку
  */