Firebase Auth vs Supabase Auth — Comparison (2026)
Head-to-head comparison: Firebase Auth vs Supabase Auth for authentication. Free tier, platform coupling, database integration, and when to choose each.
| Criteria | Firebase Auth | Supabase Auth |
|---|---|---|
| Trust Score | N/A/10 | N/A/10 |
| Free Tier | 50K MAU | 50K MAU |
| Paid Starts At | $0.0055/MAU beyond 50K | $25/month (Pro plan) |
| Best For | Google Cloud ecosystem | PostgreSQL + Row Level Security |
| Biggest Gotcha | Deep Google Cloud lock-in | RLS policies can get complex fast |
| DX Rating | 8/10 | 8/10 |
TL;DR
Choose Firebase Auth if you’re building on Google Cloud and want tight integration with Firestore, Cloud Functions, and GCP services. Choose Supabase Auth if you want PostgreSQL with Row Level Security and prefer an open-source, portable stack.
Detailed comparison
| Factor | Firebase Auth | Supabase Auth |
|---|---|---|
| Free tier MAU | 50,000 | 50,000 |
| Platform coupling | Google Cloud (Firestore, GCF) | PostgreSQL (open source, portable) |
| Database | Firestore (NoSQL) | PostgreSQL (relational) |
| Social providers | Google, Apple, Facebook, GitHub, Twitter + more | Google, Apple, Facebook, GitHub, Twitter, Discord + more |
| GDPR | Shared responsibility, US-hosted by default | EU hosting available, self-host option |
| Best for | Mobile apps on Google Cloud | Full-stack apps with PostgreSQL |
When to choose Firebase Auth
- You’re already in the Google Cloud ecosystem (Firestore, Cloud Functions, GCP)
- You’re building a mobile app and want Firebase’s mature SDKs (iOS, Android, Flutter)
- You need phone auth with SMS verification out of the box
- You want anonymous auth for gradual onboarding flows
- Your team is familiar with Firebase and NoSQL patterns
When to choose Supabase Auth
- You want auth tied directly to PostgreSQL with Row Level Security
- You prefer an open-source stack you can self-host if needed
- You need EU hosting for GDPR compliance
- You’re building with SQL and want auth users in the same database as your data
- You want to avoid vendor lock-in — Supabase Auth works with standard PostgreSQL