Supabase vs Convex: Choosing the Right BaaS 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

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

Convex

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

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.