Supabase vs Convex: Choosing the Right Backend-as-a-Service for Your Project

Backend-as-a-Service (BaaS) platforms have fundamentally changed how developers build applications. Two platforms that have gained significant traction are Supabase and Convex—both offering compelling but distinctly different approaches to backend development. This article provides an objective comparison to help you determine which platform best fits your specific needs.

Overview

Supabase is an open-source Firebase alternative built on PostgreSQL. Launched in 2020, it positions itself as a developer-friendly platform that provides a familiar SQL-based backend with modern conveniences like authentication, storage, and real-time capabilities.

Convex is a reactive backend platform that takes a fundamentally different approach. Founded by former Dropbox infrastructure engineers and launched in 2021, Convex replaces traditional SQL queries with TypeScript functions that run directly in the database, prioritizing real-time synchronization and end-to-end type safety.

Core Architecture

Supabase

Supabase is built on proven, open-source technologies assembled together:

• PostgreSQL at its core, providing a mature relational database with full SQL support
• PostgREST for auto-generated RESTful APIs
• GoTrue for JWT-based authentication
• Realtime server for WebSocket-based live updates (uses PostgreSQL’s Write-Ahead Log)
• Edge Functions running on Deno for serverless compute
• S3-compatible Storage for file management

This architecture means you’re working with familiar, battle-tested components. The tradeoff is that these components were developed independently and integrated together—they work well, but weren’t originally designed as a unified system.

Convex

Convex takes an opinionated, ground-up approach:

• Custom transactional document store designed specifically for reactive applications
• TypeScript functions (queries, mutations, actions) that replace traditional SQL
• Built-in real-time synchronization where reactivity is the default, not an add-on
• ACID transactions with serializable isolation
• Automatic caching and query optimization

Convex’s architecture was purpose-built for real-time applications. The database and compute layer are tightly integrated, meaning real-time updates flow through the same channel as reads and writes, providing stronger consistency guarantees.

Database Model

Supabase: Relational (PostgreSQL)

Supabase gives you full access to PostgreSQL—one of the most capable relational databases available:

• Complex joins, aggregations, and SQL queries
• Foreign keys and referential integrity
• Full-text search, JSON support, and PostGIS for geospatial data
• Direct SQL access and familiar tooling
• Row-level security (RLS) policies written in SQL

You manage your schema through SQL migrations, and changes follow traditional database evolution patterns. This is comfortable territory for developers with SQL experience.

Convex: Document-Based (Custom)

Convex uses a document store where you define schemas in TypeScript:

• Schema definitions using TypeScript validators
• Flexible document structure with type inference
• No SQL—all data access through TypeScript functions
• Automatic schema validation at deployment time
• Built-in vector search for AI applications

The document model is more flexible than rigid relational schemas but less suited for complex relational queries. Convex deliberately avoids SQL, betting that TypeScript functions provide a better developer experience for application development.

Real-Time Capabilities

Supabase

Real-time in Supabase works through PostgreSQL’s WAL (Write-Ahead Log):

// Subscribe to changes
const channel = supabase
  .channel('room1')
  .on('postgres_changes', { event: '*', schema: 'public', table: 'messages' }, 
    (payload) => console.log(payload))
  .subscribe()

This approach is event-driven—you receive notifications when database changes occur. It’s excellent for broadcasting updates but requires additional work to maintain consistency between the subscribed data and your application state.

Convex

Convex’s reactivity is built into the query system itself:

// React hook - automatically updates when data changes
const messages = useQuery(api.messages.list, { roomId });

The query subscription is the same mechanism as the initial data fetch. When underlying data changes, affected queries automatically re-execute and push updates to clients. There’s no separate configuration needed—if you can query it, it’s reactive.

This architectural difference becomes significant in collaborative applications where multiple users modify shared data simultaneously.

Developer Experience

Supabase

Supabase provides a polished dashboard and familiar patterns:

• Excellent web-based SQL editor and table browser
• Auto-generated REST and GraphQL APIs
• TypeScript types generated from your database schema
• Extensive documentation and large community
• Works with any language or framework through REST APIs

The learning curve is gentle if you know SQL. Edge Functions use Deno/TypeScript for custom backend logic.

Convex

Convex emphasizes TypeScript-first development:

• End-to-end type safety from database to frontend
• Schema, queries, and mutations all defined in TypeScript
• Tight integration with React (hooks like useQuery, useMutation)
• Real-time updates “just work” without additional configuration
• Functions run server-side in an isolated environment

The developer experience is exceptional for TypeScript/React developers. The tight coupling between frontend and backend types catches errors at compile time rather than runtime. However, it’s more opinionated—you’re working within Convex’s paradigm, not bringing your existing SQL knowledge.

Authentication

Supabase

Supabase offers comprehensive built-in authentication:

• Email/password, magic links, phone OTP
• Social providers (Google, GitHub, Apple, etc.)
• Enterprise SSO (SAML)
• Row-level security policies that integrate with auth
• Session management and JWT tokens

Auth is deeply integrated with the database through RLS policies:

-- Users can only read their own data
CREATE POLICY "Users can read own data" ON profiles
  FOR SELECT USING (auth.uid() = user_id);

Convex

Convex supports multiple auth approaches:

• Native Convex Auth (recently launched)
• Integration with Clerk, Auth0, and other providers
• Custom authentication via HTTP actions

Auth integrates with Convex functions through the context object:

export const getMyData = query({
  handler: async (ctx) => {
    const identity = await ctx.auth.getUserIdentity();
    if (!identity) throw new Error("Unauthorized");
    // ... query user's data
  },
});

Both platforms handle auth well, though Supabase’s deeper PostgreSQL integration may be advantageous for complex authorization rules.

Serverless Functions

Supabase Edge Functions

• Deno-based runtime
• Deploy globally on edge infrastructure
• Access to full Deno ecosystem
• Triggered via HTTP or database webhooks

Convex Functions

Convex has three function types:

• Queries: Read data, reactive by default, must be deterministic
• Mutations: Write data, transactional, must be deterministic
• Actions: Can call external APIs, non-deterministic, ideal for third-party integrations

The distinction between queries/mutations (deterministic) and actions (non-deterministic) is important—it enables Convex’s automatic caching and real-time guarantees.

Storage

Both platforms offer file storage:

Supabase Storage is S3-compatible with tight integration to auth policies. Files can have access rules based on user identity.

Convex Storage integrates with the database—files are stored with metadata in the same transactional system as your data.

Pricing Comparison

Supabase

Plan	Price	Key Limits
Free	$0/month	500MB database, 1GB storage, 50K MAUs
Pro	$25/month	8GB database, 100GB storage, 100K MAUs
Team	$599/month	Pro limits + SSO, SOC 2, team features
Enterprise	Custom	Dedicated infrastructure, HIPAA, SLAs

Usage beyond included limits incurs additional charges (database compute, bandwidth, storage).

Convex

Plan	Price	Key Limits
Free/Starter	$0/month	1M function calls, 0.5GB database, 1-6 developers
Professional	$25/developer/month	25M function calls, 50GB database, higher concurrency
Enterprise	Custom	Advanced compliance, SLAs

Convex bills primarily on function calls and compute time rather than storage-first metrics.

Key difference: Supabase’s cost scales with database size and MAUs; Convex’s cost scales with function execution and compute. Your workload characteristics determine which is more economical.

Self-Hosting and Lock-In

Supabase

Supabase is fully open source—you can self-host the entire stack. This provides a genuine escape hatch if you ever need to leave the hosted service. The underlying PostgreSQL database is completely portable.

Convex

Convex recently open-sourced its backend under FSL-1.1-Apache-2.0 licensing. Self-hosting is possible with Docker and Postgres, though the hosted experience is more polished. Migration away from Convex requires more work since it uses a custom database system rather than standard PostgreSQL.

AI and Vector Search

Both platforms have invested in AI capabilities:

Supabase integrates with pgvector for vector storage and similarity search. You can combine vector queries with standard SQL operations.

Convex offers built-in vector search and RAG (Retrieval-Augmented Generation) components, positioning itself strongly for AI-native applications. The Convex team reports that 80% of applications built on the platform are AI-powered.

Performance Characteristics

Real-world benchmarks suggest:

• Convex typically achieves sub-50ms read/write latency even at high concurrency (5,000+ connections)
• Supabase/PostgreSQL handles large analytical queries efficiently but may see 100-200ms p99 latencies under similar concurrent loads

Convex is optimized for OLTP (Online Transaction Processing)—frequent small transactions typical of interactive applications. Supabase/PostgreSQL is more versatile, handling both OLTP and OLAP (analytical) workloads.

When to Choose Supabase

Supabase is likely the better choice when:

• You have existing SQL knowledge and want to leverage it
• Your data model is highly relational with complex joins
• You need advanced PostgreSQL features (PostGIS, full-text search, stored procedures)
• You require a self-hostable, open-source solution with proven technology
• Your team prefers REST APIs and works across multiple languages/frameworks
• You’re building traditional CRUD applications where real-time is a “nice to have”
• You need extensive compliance options and enterprise features
• You want maximum flexibility and minimal vendor lock-in

Example use cases:

• SaaS applications with complex data relationships
• Applications requiring geospatial queries
• Projects where you anticipate needing to migrate to raw PostgreSQL
• Teams with strong SQL expertise
• Multi-platform applications (web, mobile, desktop with different tech stacks)

When to Choose Convex

Convex is likely the better choice when:

• You’re building highly interactive, real-time applications
• Your team is TypeScript-first (especially React/Next.js developers)
• End-to-end type safety is a priority
• Real-time collaboration features are core to your product
• You want to move fast without configuring WebSockets, caching, or sync logic
• You’re building AI-powered applications with vector search needs
• You prefer writing backend logic as functions rather than SQL
• Your data model fits a document-based approach

Example use cases:

• Collaborative tools (like Notion, Figma)
• Real-time dashboards and live data applications
• Chat applications and messaging platforms
• AI-powered applications with streaming responses
• Multiplayer games and interactive experiences
• Projects where the frontend and backend team are the same people

Scenarios Where Either Works Well

Some projects could succeed equally well with either platform:

• Standard web applications with moderate real-time needs
• Internal tools and admin dashboards
• MVPs and prototypes (both have generous free tiers)
• Applications with moderate scale requirements

Migration Considerations

From Supabase: Standard PostgreSQL data is portable. Export via pg_dump and import into any PostgreSQL-compatible system.

From Convex: Data exports are available in JSON format. Moving to a relational database requires schema translation and potentially significant application changes due to the different data model.

Summary

Factor	Supabase	Convex
Database	PostgreSQL (relational)	Custom document store
Query Language	SQL	TypeScript functions
Real-time	Event-based (WAL)	Reactive queries (built-in)
Type Safety	Generated from schema	End-to-end native
Self-hosting	Fully supported, mature	Available, newer
Learning Curve	Low if you know SQL	Low if you know TypeScript
Best For	SQL fans, complex relations	TypeScript devs, real-time apps
Open Source	Yes (Apache 2.0)	Yes (FSL-1.1-Apache-2.0)
Primary Cost Driver	Database size, MAUs	Function calls, compute

Conclusion

Neither platform is objectively “better”—they represent different philosophies about backend development.

Supabase bets on PostgreSQL’s proven capabilities and the value of SQL’s ubiquity. It’s the conservative choice in the best sense: you’re building on technology that has decades of production use. If something goes wrong, you can always fall back to raw PostgreSQL.

Convex bets that a purpose-built reactive system provides a fundamentally better developer experience for modern applications. It’s the innovative choice: you’re trading the comfort of familiar SQL for tighter integration and automatic real-time behavior.

Your choice should depend on your team’s expertise, your application’s requirements, and your preferences around technology adoption. Both platforms are well-funded, actively developed, and suitable for production use. Try both free tiers on a small project—the hands-on experience will clarify which approach resonates with how you like to build software.