Clerk vs Firebase
User management and authentication as a service
vs. Google's mobile & web app development platform
Pricing tiers
Clerk
Free
50k MAU included. No SSO/SAML. Perfect for side projects and early prototypes.
Free
Pro
$25/mo (or $20/mo annual). 50k MAU, $0.02 each after. 1 enterprise SSO connection per app. Webhooks, JWT templates, custom session duration.
$25/mo
Business
$300/mo (or $250/mo annual). Advanced organizations, enhanced support, additional enterprise features.
$300/mo
Enterprise
Custom. Volume MAU discounts, SLA, workspace-wide SAML SSO, dedicated support.
Custom
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
Free-tier quotas head-to-head
Comparing hobby on Clerk vs spark on Firebase.
| Metric | Clerk | Firebase |
|---|---|---|
| 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 |
| hosting storage gb | — | 10 GB |
| hosting transfer gb month | — | 10.8 GB/month |
| mao | 100 orgs/month | — |
| mau | 50000 users/month | — |
| phone sms verifications day | — | 10 sms/day |
| rtdb connections | — | 100 connections |
| rtdb downloaded gb month | — | 10 GB/month |
| rtdb stored gb | — | 1 GB |
| sso connections | 0 connections | — |
| storage downloaded gb day | — | 1 GB/day |
| storage gb | — | 5 GB |
| storage operations day | — | 50000 ops/day |
Features
Clerk · 15 features
- Account Portal — Hosted sign-in/user profile pages at accounts.yourapp.com — zero UI code, fully …
- Bot Protection — Cloudflare Turnstile CAPTCHA integrated into sign-up.
- Clerk Billing — Built-in Stripe-powered billing: subscriptions, plans, proration — ties directly…
- Enterprise SSO (SAML/OIDC) — SAML and OIDC for enterprise customers. Per-domain connection. Pro+ (1 included)…
- Impersonation — Act as a user from dashboard to debug. Logged.
- JWT Templates — Custom JWT issuance for third-party backends (Supabase, Hasura, Firebase, Convex…
- Machine Tokens (M2M) — API keys and machine tokens for service-to-service auth in addition to user sess…
- Multi-Factor Auth — TOTP (authenticator apps), SMS OTP, backup codes. Forced or optional per user.
- Organizations (B2B) — Multi-tenant orgs with roles, permissions, invitations, domain allowlist, and pe…
- Passkeys (WebAuthn) — Passwordless passkey sign-in with per-device biometrics.
- Prebuilt Components — Drop-in React components: <SignIn/>, <SignUp/>, <UserButton/>, <OrganizationSwit…
- Sessions — Server-side session tokens. Sliding expiration by default; configurable absolute…
- User Management — Full user CRUD, metadata (public/private/unsafe), email/phone verification, ban/…
- Waitlist Mode — Collect sign-ups before opening the app. Approve waitlist entries to activate ac…
- Webhooks — Events: user.created/updated/deleted, session.created, organization.* — delivere…
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, …
Developer interfaces
| Kind | Clerk | Firebase |
|---|---|---|
| CLI | — | Firebase CLI |
| SDK | @clerk/astro, @clerk/backend / @clerk/clerk-sdk-node, @clerk/chrome-extension, @clerk/clerk-expo, @clerk/clerk-js (vanilla), @clerk/clerk-react, @clerk/clerk-react-native, @clerk/nextjs, @clerk/nuxt, @clerk/remix, clerk-sdk-go, clerk-sdk-python, clerk-sdk-ruby, @clerk/tanstack-start, @clerk/vue | 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 |
| REST | Backend REST API, Frontend API | Auth REST API, Cloud Storage REST, Firebase Management API, Firestore REST API, Realtime Database REST |
| MCP | Clerk MCP | Firebase MCP Server |
| OTHER | Webhooks (Svix) | Firestore gRPC, Realtime Database WebSocket |
Staxly is an independent catalog of developer platforms. Outbound links to Clerk and Firebase are plain references to their official websites. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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