Firebase vs Knock
Google's mobile & web app development platform
vs. Notifications-as-a-service: in-app feeds, email, push, SMS, chat via one API
Pricing tiers
Firebase
Spark (No-cost)
Free tier with generous quotas. No credit card required. Cannot exceed free quotas.
Free
Blaze (Pay as you go)
Usage-based billing. Includes Spark quotas free, then pay Google Cloud rates. Required for Cloud Functions outbound networking, scheduled jobs, some extensions.
Custom
Knock
Developer
Free forever. 10K messages, 500 guide users, 500 AI credits/month.
$0 base (usage-based)
Starter
$250/mo. 50K messages, 2.5K guide users, 2K AI credits. Remove branding.
$250/mo
Enterprise
Custom pricing. White-label, i18n, data warehouse, Datadog, SCIM, SAML, HIPAA/BAA.
Custom
Free-tier quotas head-to-head
Comparing spark on Firebase vs starter on Knock.
| Metric | Firebase | Knock |
|---|---|---|
| auth mau | 50000 users/month | — |
| firestore deletes per day | 20000 docs/day | — |
| firestore egress gib month | 10 GiB/month | — |
| firestore reads per day | 50000 docs/day | — |
| firestore storage gib | 1 GiB | — |
| firestore writes per day | 20000 docs/day | — |
| functions cpu seconds | 200000 CPU-sec/month | — |
| functions gb seconds | 400000 GB-sec/month | — |
| functions invocations | 2000000 invocations/mo | — |
| functions outbound gb | 5 GB/month | — |
| guide users | — | 2500 users |
| guide users overage | — | $0.05/user USD/user |
| hosting storage gb | 10 GB | — |
| hosting transfer gb month | 10.8 GB/month | — |
| messages monthly | — | 50000 messages/mo |
| messages overage | — | $0.005/message USD/message |
| phone sms verifications day | 10 sms/day | — |
| rtdb connections | 100 connections | — |
| rtdb downloaded gb month | 10 GB/month | — |
| rtdb stored gb | 1 GB | — |
| storage downloaded gb day | 1 GB/day | — |
| storage gb | 5 GB | — |
| storage operations day | 50000 ops/day | — |
Features
Firebase · 20 features
- A/B Testing — Experiments on Remote Config params, FCM notifications, and Analytics events. Ba…
- App Check — Attestation service: only requests from authentic, untampered app instances reac…
- App Hosting — Managed hosting for modern web apps (Next.js, Angular, SvelteKit). Git-based dep…
- Cloud Firestore — Serverless NoSQL document database. Real-time sync, ACID transactions, offline p…
- Cloud Functions — Serverless functions (Node.js/Python). Trigger on HTTP, Firestore, RTDB, Auth, S…
- Cloud Storage — Object storage for user files. Built on GCS. Security rules + signed URLs. Resum…
- Crashlytics — Real-time crash reporting for iOS/Android/Unity/Flutter. Stack traces, breadcrum…
- Data Connect — GraphQL API backed by Cloud SQL for PostgreSQL. Type-safe SDK generation. Previe…
- Dynamic Links — Deep links that survive app install. NOTE: deprecated, shutdown Aug 2025 — migra…
- FCM Topics — Publish/subscribe messaging: devices subscribe to topic names; backend sends one…
- Firebase AI Logic — Client-side SDK to call Gemini models directly from mobile/web. Formerly "Vertex…
- Firebase Authentication — Drop-in auth: email/password, phone, anonymous, 10+ federated providers, custom …
- Firebase Cloud Messaging — Push notifications for iOS, Android, Web (APNs/FCM transports). Topics, device g…
- Firebase Extensions — Pre-packaged Cloud Functions + config: Stripe, Algolia search, image resize, tra…
- Firebase Hosting — Static + dynamic hosting with global CDN. Preview channels, atomic deploys, rewr…
- Genkit — Open-source AI app framework. Unified API for Gemini, OpenAI, Ollama; tools, RAG…
- Google Analytics for Firebase — Free unlimited event tracking with audience building. BigQuery export on Blaze. …
- Performance Monitoring — App startup, HTTP network, and custom traces. Integrates with Google Analytics e…
- Realtime Database — Low-latency JSON tree database with WebSocket sync. Best for high-frequency pres…
- Remote Config — Feature flags / parameterized config with conditional targeting (user property, …
Knock · 13 features
- AI Agents — Autonomous notification drafting & workflow generation.
- Batch + Digest — Group notifications into digests on schedule or window.
- Chat — Slack, Microsoft Teams, Discord.
- Email — Send via SendGrid/Postmark/Resend/Mailgun/AWS SES as relays.
- Guides — In-product messaging, announcements, modals, banners.
- i18n / Localization — Translate templates by user locale.
- In-App Feed — Notification inbox with React/Vue/iOS/Android drop-in components.
- Multi-tenancy — Per-tenant branding, preferences, quiet hours.
- Outbound Webhooks — Subscribe to delivery events.
- Preferences — User + tenant preference center with granular controls.
- Push — iOS (APNs), Android (FCM), Expo, Web Push.
- SMS — Twilio, MessageBird, Telnyx, Vonage as providers.
- Workflows — Visual notification orchestration (branch, batch, delay, throttle).
Developer interfaces
| Kind | Firebase | Knock |
|---|---|---|
| CLI | Firebase CLI | Knock CLI |
| SDK | Admin SDK (Go), Admin SDK (Java), Admin SDK (Node.js), Admin SDK (Python), Android SDK, Apple Platforms SDK, Flutter SDK (FlutterFire), JavaScript SDK, Unity SDK | knockapi (Python), knockapi (Ruby), knock-elixir, knock-go, knock-java, @knocklabs/node, @knocklabs/react |
| REST | Auth REST API, Cloud Storage REST, Firebase Management API, Firestore REST API, Realtime Database REST | Knock REST API |
| MCP | Firebase MCP Server | Knock MCP Server |
| OTHER | Firestore gRPC, Realtime Database WebSocket | Outbound Webhooks |
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