Supabase vs Firebase Authentication: Which is Better for Your App in 2026?

Choosing between Supabase and Firebase for authentication can make or break your project timeline. Both are powerful Backend-as-a-Service (BaaS) platforms, but they take fundamentally different approaches. Let's break down exactly which one you should use.

Quick Comparison Table#

| Feature | Supabase | Firebase | |---------|----------|----------| | Database | PostgreSQL (SQL) | Firestore (NoSQL) | | Open Source | ✅ Yes | ❌ No | | Self-Hosting | ✅ Yes | ❌ No | | Pricing Model | Predictable, usage-based | Can spike unexpectedly | | Auth Methods | Email, OAuth, Magic Links, Phone | Email, OAuth, Phone, Anonymous | | Row Level Security | ✅ Built-in (RLS) | Manual security rules | | Real-time | PostgreSQL subscriptions | Firestore real-time listeners | | Learning Curve | Moderate (SQL knowledge helps) | Easy (NoSQL, familiar API) | | Vendor Lock-in | Low (standard PostgreSQL) | High (proprietary) | | Best For | SQL lovers, complex queries | Quick prototypes, NoSQL fans |

When to Use Supabase#

1. You Need SQL and Complex Queries#

Supabase uses PostgreSQL, which means you get:

• Complex joins across multiple tables
• Full-text search out of the box
• Powerful aggregations and analytics
• ACID compliance for transactions

// Complex query with joins in Supabase
const { data, error } = await supabase
  .from('users')
  .select(`
    *,
    posts (
      id,
      title,
      comments (count)
    )
  `)
  .eq('status', 'active')
  .order('created_at', { ascending: false })
  .limit(10);

2. You Want to Avoid Vendor Lock-in#

Supabase is open source and uses standard PostgreSQL:

• Export your data anytime
• Self-host if needed
• Switch providers easily
• No proprietary APIs

3. You Need Predictable Pricing#

Supabase pricing is straightforward:

• Free tier: 500MB database, 2GB bandwidth
• Pro: $25/month for 8GB database, 50GB bandwidth
• No surprise bills from read/write operations

4. You're Building a SaaS with Multi-Tenancy#

Row Level Security (RLS) makes multi-tenant apps simple:

-- RLS policy for user-specific data
CREATE POLICY "Users can only see their own data"
ON user_data
FOR SELECT
USING (auth.uid() = user_id);

When to Use Firebase#

1. You Need to Ship Fast#

Firebase has the fastest setup:

• Authentication in 5 minutes
• No database schema design needed
• Excellent documentation
• Huge community

// Firebase auth setup is incredibly simple
import { getAuth, signInWithPopup, GoogleAuthProvider } from 'firebase/auth';

const auth = getAuth();
const provider = new GoogleAuthProvider();

signInWithPopup(auth, provider)
  .then((result) => {
    const user = result.user;
    console.log('Signed in:', user);
  });

2. You're Building a Mobile App#

Firebase has superior mobile SDKs:

• Native iOS and Android support
• Offline persistence built-in
• Push notifications integrated
• Crashlytics and Analytics

3. You Prefer NoSQL#

If you think in documents rather than tables:

• Flexible schema
• Nested data structures
• No migrations needed
• Easy to understand

4. You Need Google Ecosystem Integration#

Firebase integrates seamlessly with:

• Google Analytics
• Google Cloud Functions
• Google Cloud Storage
• BigQuery for analytics

Feature-by-Feature Comparison#

Authentication Methods#

Supabase:

• ✅ Email/Password
• ✅ Magic Links (passwordless)
• ✅ OAuth (Google, GitHub, GitLab, Bitbucket, Azure, etc.)
• ✅ Phone/SMS
• ✅ SAML SSO (Enterprise)
• ❌ Anonymous auth

Firebase:

• ✅ Email/Password
• ✅ Email Link (passwordless)
• ✅ OAuth (Google, Facebook, Twitter, GitHub, Apple, Microsoft)
• ✅ Phone/SMS
• ✅ Anonymous auth
• ✅ Custom auth tokens
• ❌ SAML SSO (requires Identity Platform upgrade)

Performance#

Supabase:

• Database queries: 10-50ms (with proper indexes)
• Auth token verification: 5-10ms
• Real-time subscriptions: WebSocket-based
• Global CDN for static assets

Firebase:

• Firestore reads: 50-200ms (depending on region)
• Auth token verification: 10-20ms
• Real-time listeners: WebSocket-based
• Global CDN included

Developer Experience#

Supabase:

// Type-safe queries with TypeScript
import { createClient } from '@supabase/supabase-js';
import { Database } from './database.types';

const supabase = createClient<Database>(
  process.env.NEXT_PUBLIC_SUPABASE_URL!,
  process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!
);

// Auto-complete for table names and columns
const { data } = await supabase
  .from('posts')
  .select('id, title, author:users(name)')
  .eq('published', true);

Firebase:

// Simple but less type-safe
import { collection, query, where, getDocs } from 'firebase/firestore';

const q = query(
  collection(db, 'posts'),
  where('published', '==', true)
);

const querySnapshot = await getDocs(q);
querySnapshot.forEach((doc) => {
  console.log(doc.id, doc.data());
});

Pricing Comparison (Monthly)#

Supabase:

• Free: $0 (500MB DB, 2GB bandwidth, 50MB file storage)
• Pro: $25 (8GB DB, 50GB bandwidth, 100GB storage)
• Team: $599 (no limits, priority support)

Firebase:

• Spark (Free): $0 (1GB storage, 10GB bandwidth, 50K reads/day)
• Blaze (Pay-as-you-go):
  • $0.18 per GB storage
  • $0.12 per GB bandwidth
  • $0.06 per 100K reads
  • Can get expensive quickly with scale

Security#

Supabase:

• Row Level Security (RLS) at database level
• Policies written in SQL
• Fine-grained control
• Harder to make mistakes

-- Example: Users can only update their own profile
CREATE POLICY "Users can update own profile"
ON profiles
FOR UPDATE
USING (auth.uid() = id)
WITH CHECK (auth.uid() = id);

Firebase:

• Security rules in custom syntax
• Applied at collection/document level
• Easier to get started
• Easier to make security mistakes

// Firebase security rules
rules_version = '2';
service cloud.firestore {
  match /databases/{database}/documents {
    match /users/{userId} {
      allow read, write: if request.auth != null && request.auth.uid == userId;
    }
  }
}

Real-World Examples#

Example 1: SaaS Dashboard (Use Supabase)#

You're building a project management tool with:

• Complex reporting queries
• Multi-tenant architecture
• Need for data exports
• Budget constraints

Why Supabase wins:

• RLS handles multi-tenancy elegantly
• SQL makes reporting queries simple
• Predictable $25/month pricing
• Easy data exports for customers

Example 2: Social Media App (Use Firebase)#

You're building an Instagram-like app with:

• Heavy mobile focus
• Real-time feeds
• Image uploads
• Push notifications

Why Firebase wins:

• Superior mobile SDKs
• Built-in push notifications
• Excellent image storage
• Real-time updates are simpler

Example 3: E-commerce Platform (Use Supabase)#

You're building an online store with:

• Complex product relationships
• Inventory management
• Order processing
• Analytics requirements

Why Supabase wins:

• SQL handles complex relationships
• Transactions for order processing
• Better for analytics queries
• Lower costs at scale

Migration Guide#

From Firebase to Supabase#

1. Export Firestore data

gcloud firestore export gs://your-bucket/firestore-export

2. Design PostgreSQL schema

CREATE TABLE users (
  id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
  email TEXT UNIQUE NOT NULL,
  created_at TIMESTAMPTZ DEFAULT NOW()
);

3. Migrate authentication

// Import users to Supabase
const { data, error } = await supabase.auth.admin.createUser({
  email: user.email,
  password: temporaryPassword,
  email_confirm: true
});

From Supabase to Firebase#

1. Export PostgreSQL data

pg_dump -h db.your-project.supabase.co -U postgres > backup.sql

2. Transform to Firestore format

// Convert SQL rows to Firestore documents
const batch = db.batch();
users.forEach(user => {
  const docRef = db.collection('users').doc(user.id);
  batch.set(docRef, user);
});
await batch.commit();

Common Mistakes to Avoid#

With Supabase:#

1. Forgetting RLS policies - Your data is public by default
2. Not using indexes - Queries can be slow without proper indexes
3. Ignoring connection pooling - Can hit connection limits

With Firebase:#

1. Poor security rules - Easy to expose data accidentally
2. Not optimizing reads - Costs can spiral with inefficient queries
3. Ignoring offline persistence - Mobile apps need offline support

Conclusion#

Choose Supabase if:

• You need SQL and complex queries
• You want to avoid vendor lock-in
• You're building a SaaS or B2B product
• You need predictable pricing
• You prefer open source

Choose Firebase if:

• You need to ship extremely fast
• You're building a mobile-first app
• You prefer NoSQL and flexible schemas
• You need Google ecosystem integration
• You want the easiest possible setup

Both are excellent choices. Supabase is better for complex, data-heavy applications where SQL shines. Firebase is better for rapid prototyping and mobile apps where speed to market matters most.

Related Articles#

• Supabase Authentication Complete Guide
• Fix Supabase Auth Session Not Persisting
• Implement Social Auth with Supabase
• Building SaaS with Next.js and Supabase

FAQ#

Can I use both Supabase and Firebase together?#

Yes, but it's not recommended. You'd be paying for two backends and managing two authentication systems. Pick one based on your primary needs.

Is Supabase really free to self-host?#

Yes, Supabase is fully open source. You can self-host on your own infrastructure, though you'll need to manage updates, backups, and scaling yourself.

Which has better TypeScript support?#

Supabase has superior TypeScript support with auto-generated types from your database schema. Firebase's TypeScript support is good but not as comprehensive.

Can I migrate from Firebase to Supabase without downtime?#

Yes, with careful planning. Run both systems in parallel, gradually migrate users, then switch over. Expect 2-4 weeks for a smooth migration.

Which is more secure?#

Both are secure when configured correctly. Supabase's RLS is harder to misconfigure, while Firebase's security rules are more flexible but easier to get wrong.