Firebase vs Auth0
Google's mobile & web app development platform
vs. Customer identity platform from Okta
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
Auth0
B2C Essentials
Starting at 500 MAUs. Pro MFA, RBAC, passwordless, SAML, 10 orgs.
$35/mo
B2B Essentials
Unlimited orgs, 3 SSO connections, RBAC.
$150/mo
B2C Professional
Starting at 500 MAUs. Includes attack protection, custom DB, enterprise MFA.
$240/mo
B2B Professional
5+ SSO connections, attack protection, custom DB.
$800/mo
Enterprise
Custom. 99.99% SLA, dedicated support.
Custom
Free-tier quotas head-to-head
Comparing spark on Firebase vs b2c-essentials on Auth0.
| Metric | Firebase | Auth0 |
|---|---|---|
| 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 | — |
| mau start | — | 500 MAU |
| 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 conns |
| 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, …
Auth0 · 14 features
- Attack Protection — Bot detection, brute-force protection, breached-password detection, suspicious I…
- Auth0 Actions — Node.js + TS hooks that run during auth flows (login, post-login, signup, MFA). …
- Auth0 FGA (OpenFGA) — Fine-grained relationship-based authorization (ReBAC). Based on Google Zanzibar.
- Custom Database — BYO user DB: scripts in Actions read from your database and create Auth0 users o…
- Custom Domain — Serve auth at auth.yourbrand.com with managed cert.
- Enterprise SSO — SAML 2.0 + OIDC + AD/LDAP enterprise connections. Per-tenant or per-org.
- Log Streaming — Stream tenant logs to Datadog, Splunk, Sumo Logic, Azure Sentinel, HTTP, Mixpane…
- Machine-to-Machine — Client-credentials grant for backend services.
- Multi-Factor Auth — SMS, Voice, Email, TOTP, WebAuthn (biometrics), Push (Guardian app), Duo.
- Organizations — Multi-tenant B2B: orgs with invitations, roles, branding, enterprise connections…
- Passkeys — FIDO2/WebAuthn passkey sign-in.
- Passwordless — Email magic link + code, SMS code, WebAuthn.
- RBAC — Roles, permissions, API scopes — attach to users or orgs.
- Universal Login — Hosted login page with customization, multi-factor flows, passwordless, social, …
Developer interfaces
| Kind | Firebase | Auth0 |
|---|---|---|
| CLI | Firebase CLI | Auth0 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 | Auth0 Android, Auth0 iOS/Swift, @auth0/nextjs-auth0, Auth0 React SDK, Auth0 SPA.js SDK, Go Auth0 SDK, Node Auth0 Backend SDK, Python Auth0 SDK |
| REST | Auth REST API, Cloud Storage REST, Firebase Management API, Firestore REST API, Realtime Database REST | Authentication API, Management API |
| MCP | Firebase MCP Server | — |
| OTHER | Firestore gRPC, Realtime Database WebSocket | — |
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