Convex vs Supabase vs Firebase: Real-Time Backend Showdown 2025

The Backend-as-a-Service Evolution

Choosing the right backend platform is crucial for modern web applications. In 2025, three platforms dominate the real-time backend space: Convex, Supabase, and Firebase.

Platform Overview

Convex: The Reactive Database

Convex represents a new paradigm in backend development with its reactive, TypeScript-first approach.

Key Features:

• Reactive Queries: Automatic real-time updates
• TypeScript End-to-End: Full type safety from database to frontend
• ACID Transactions: Strong consistency guarantees
• Serverless Functions: Integrated backend logic
• File Storage: Built-in file handling

Unique Selling Point: Zero-config real-time - queries automatically update when data changes.

Supabase: The Open Source Firebase Alternative

Supabase provides a PostgreSQL-based platform with a comprehensive feature set.

Key Features:

• PostgreSQL: Full SQL database power
• Row Level Security: Fine-grained access control
• Real-time Subscriptions: Listen to database changes
• Auth: Built-in authentication
• Edge Functions: Deno-based serverless

Unique Selling Point: Open source and self-hostable with full PostgreSQL capabilities.

Firebase: The Google Ecosystem

Firebase offers a mature, battle-tested platform deeply integrated with Google Cloud.

Key Features:

• Firestore: NoSQL document database
• Realtime Database: JSON-based real-time sync
• Cloud Functions: Node.js serverless
• Authentication: Comprehensive auth providers
• Hosting: Fast static hosting with CDN

Unique Selling Point: Best mobile SDK support and Google Cloud integration.

Feature Comparison

Real-Time Capabilities

Convex

// Queries are automatically reactive
const messages = useQuery(api.messages.list);
// UI updates automatically when data changes

Convex's reactive model means you don't need to set up subscriptions - queries automatically update when underlying data changes.

Supabase

// Subscribe to changes
const subscription = supabase
  .channel('messages')
  .on('postgres_changes', { event: '*', schema: 'public' }, 
    (payload) => console.log(payload))
  .subscribe();

Supabase requires explicit subscription setup but offers fine-grained control over what changes to listen for.

Firebase

// Real-time listener
const unsubscribe = onSnapshot(
  collection(db, 'messages'),
  (snapshot) => {
    snapshot.docChanges().forEach((change) => {
      // Handle changes
    });
  }
);

Firebase's real-time capabilities are mature and well-optimized for mobile applications.

Developer Experience

Convex

• Pros: Best TypeScript integration, automatic reactivity, simple mental model
• Cons: Newer platform, smaller community, no SQL

Supabase

• Pros: Familiar PostgreSQL, excellent documentation, open source
• Cons: Real-time requires setup, more complex architecture

Firebase

• Pros: Mature ecosystem, excellent mobile SDKs, extensive documentation
• Cons: NoSQL limitations, vendor lock-in, complex pricing

Pricing Comparison

Free Tier Comparison

Paid Tier (Estimated Monthly Cost for Medium App)

Firebase's usage-based pricing can become unpredictable at scale.

When to Choose Each

Choose Convex When

• Building React/Next.js applications
• Type safety is a priority
• Want automatic real-time without configuration
• Building collaborative features
• Prefer serverless architecture

Choose Supabase When

• Need full PostgreSQL capabilities
• Want to self-host
• Have existing SQL expertise
• Need complex queries and joins
• Prefer predictable pricing

Choose Firebase When

• Building mobile-first applications
• Already in Google Cloud ecosystem
• Need mature, battle-tested platform
• Want extensive third-party integrations
• Building with Flutter or React Native

Migration Considerations

From Firebase to Supabase

• Restructure data from NoSQL to relational
• Migrate authentication (user export available)
• Rewrite queries from Firestore to SQL
• Update real-time subscriptions

From Firebase to Convex

• Map Firestore collections to Convex tables
• Convert Cloud Functions to Convex functions
• Simplify real-time code (automatic in Convex)
• Migrate authentication to Convex or Clerk

From Supabase to Convex

• Convert SQL schemas to Convex tables
• Rewrite queries as Convex functions
• Remove explicit subscriptions (automatic)
• Migrate Row Level Security to Convex rules

Performance Benchmarks

Based on real-world testing:

Our Recommendation

For new web applications in 2025, Convex offers the best developer experience with its automatic reactivity and TypeScript integration. It's particularly well-suited for Next.js applications.

For teams with SQL expertise or self-hosting requirements, Supabase provides the most flexibility with full PostgreSQL capabilities.

For mobile-first applications or teams already in the Google ecosystem, Firebase remains a solid choice with its mature SDKs and extensive features.

Compare these platforms with our Compare tool or explore backend options in our Tools directory.

Sources

• Convex Documentation
• Supabase Documentation
• Firebase Documentation
• Supabase vs Firebase Comparison