21/50vs20.5/50
FEATURE
FIREBASE AUTH
SUPABASE AUTH
OVERALL_SCORE
21/50
20.5/50
API_QUALITY
EXCELLENT ████
EXCELLENT ████
API_SCORE
10/10
10/10
GTM_RELEVANCE
11/20
10.5/20
CATEGORY
AUTH & INFRASTRUCTURE
AUTH & INFRASTRUCTURE
PRICING
FREEMIUM
FREEMIUM
FREE_TIER
[YES]
[YES]
REST_API
[YES]
[YES]
WEBHOOKS
[---]
[---]
GRAPHQL
[---]
[---]
OAUTH
[YES]
[YES]
COMPLEXITY
HARD
HARD
LEARNING
MEDIUM
MEDIUM
WEBHOOK_REL
EXCELLENT
EXCELLENT
// VERDICT
OVERALL_SCORE:FIREBASE AUTH
API_QUALITY:TIE
GTM_RELEVANCE:FIREBASE AUTH
EASE_OF_USE:TIE
VALUE (FREE):TIE
Strengths & Weaknesses
Firebase Auth
Generous free tier covering up to 50,000 monthly active users for email, password, and social authentication methods
Drop-in FirebaseUI component handles complex authentication flows, account recovery, and linking out of the box
Seamless integration with Firebase ecosystem services like Firestore, Cloud Functions, and Cloud Storage
Supports wide range of authentication methods including email, phone, social providers, and anonymous auth
Phone authentication can become expensive at scale with per-SMS charges ranging from $0.01-$0.06 per verification
Strong vendor lock-in with Google Cloud makes migration to other platforms architecturally challenging
Limited customization options and no self-hosting capability for teams needing infrastructure control
Supabase Auth
Postgres-native architecture stores users directly in your database, enabling seamless RLS integration and data relationships
Extremely generous free tier (50,000 MAUs) with very low per-user costs ($0.00325/MAU) after that
Zero additional vendor lock-in if already using Supabase—auth comes bundled with the platform
Strong developer experience with modern SDKs, clear documentation, and fast integration for Next.js/React apps
Requires using Supabase as your backend platform—not a standalone auth solution for existing architectures
Row Level Security policies can become complex to manage and debug as authorization rules grow
Less mature enterprise features compared to Auth0/Okta, with fewer advanced compliance certifications