Polar vs Firebase
Merchant of Record for devs — usage-based billing, MoR, 4% + 40¢
vs. Google's mobile & web app development platform
Pricing tiers
Polar
Pay-as-you-go
4% + 40¢ per transaction. Cheapest Merchant-of-Record. No monthly or setup fees.
$0 base (usage-based)
Enterprise
Custom. Volume discounts for high-growth teams.
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 payg on Polar vs spark on Firebase.
| Metric | Polar | 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 |
| 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
Polar · 15 features
- Customer Portal — Self-serve subscription management.
- Feature Flags — Simple flag mgmt tied to subscription tiers.
- Framework Adapters — Next.js, BetterAuth, TS, Python, Laravel, Ruby, 11+ more.
- Fraud Protection — Chargeback + fraud handling included.
- GitHub Sponsors Import — Import existing sponsors to Polar.
- Global Tax Compliance — VAT/GST/sales tax filed by Polar.
- Hosted Checkout — Polar-hosted + embeddable checkout.
- License Keys — Generate + validate license keys for software.
- Metering — Track API calls, tokens, custom units.
- One-off Purchases — Single purchases + digital downloads.
- Open-Source Backend — Full platform code on GitHub.
- Sandbox Environment — Test transactions without charging.
- Subscriptions — Tiered plans with upgrades/downgrades.
- Usage-Based Billing — Event ingestion → meter → invoice.
- Webhooks — Resource events with HMAC signatures.
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 | Polar | Firebase |
|---|---|---|
| CLI | — | Firebase CLI |
| SDK | polar-sdk-python, @polar-sh/better-auth, @polar-sh/nextjs, @polar-sh/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 |
| REST | Polar REST API | Auth REST API, Cloud Storage REST, Firebase Management API, Firestore REST API, Realtime Database REST |
| MCP | Polar MCP | Firebase MCP Server |
| OTHER | Polar Checkout, Polar Webhooks | Firestore gRPC, Realtime Database WebSocket |
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