Convex vs Supabase: which backend should you build your ai app on?

the full guide

quick answer: for most ai apps it's Supabase: #1 of 5 on our backends board at 9.0/10, because you get a real Postgres database, auth, storage and pgvector in one project, and it's all plain SQL underneath. Convex is #5 (7.5/10) and it's the better pick for one specific job: realtime apps written end to end in TypeScript, where the UI updates itself the moment the data changes.

the short version

ranks and scores come straight from our backend board, and nobody pays to move up it.

why Supabase ranks higher

it's Postgres, so nothing is exotic. every project is a dedicated Postgres database. connect with psql, Prisma, Drizzle or any Postgres client, and auth, storage, realtime and edge functions sit alongside it if you want them. unused bits cost nothing. your coding agent already knows SQL, and so does whoever inherits the project.

the ai bits are in the box. pgvector for embeddings, with Supabase's own guides for semantic, keyword and hybrid search, so your app data and your vectors live in the same database and the same query. no second vector service to pay for or keep in sync.

auth is generous. 50,000 monthly active users on the free plan and 100,000 on Pro before you pay per user.

the catch: free projects pause after a week with no activity, and you get two active free projects. Supabase Pro starts at $25 a month and includes $10 of compute credit, which covers one Micro instance; every extra project adds its own compute. spend caps are on by default on Pro, which is the right default.

where Convex wins

realtime is the whole point, not a feature. a Convex query is a TypeScript function, and the client subscribes to it. when any data that query read changes, Convex reruns it and pushes the new result down the WebSocket. useQuery in React and the component just updates. no subscription plumbing, no cache invalidation.

strong guarantees, less code. mutations are transactions with no begin or end to write, they retry automatically on conflicts, and Convex says your app never sees inconsistent data. queries are read-only, network calls go in actions (that's where you call your LLM), and there's a scheduler and crons for background jobs.

it suits ai-written code. end-to-end types and no SQL means your coding agent writes the backend in the same TypeScript as the front end. Convex makes that pitch itself; we'd say it's fair for TypeScript shops, less so if your team thinks in SQL.

the honest bit: it's not Postgres. it's a document-relational database (the cloud runs on PlanetScale MySQL underneath), so your SQL, your ORM and most of your Postgres tooling don't come with you. the free plan includes 0.5 GB of database storage and 1M function calls a month, Convex Professional is $25 per developer a month, and Business and Enterprise has a $2,500 monthly minimum, which is a big jump if you outgrow Convex Professional.

which should you pick?

• a SaaS or ai app with users, files and embeddings: Supabase
• RAG or semantic search over your own data: Supabase, pgvector next to your tables
• you want SQL and an exit door: Supabase. it's Postgres
• a collaborative or live-updating app (chat, multiplayer, dashboards) in TypeScript: Convex
• you never want to write SQL or manage subscriptions: Convex
• just want serverless Postgres with branches per PR, no extras: Neon is #4 (8.0/10). see Neon vs Supabase
• a long-running agent or worker that needs a server, not a database: Railway (#3)

the rest of the field

faq

is Convex better than Supabase?

not on our board: Supabase is #1 (9.0/10) and Convex #5 (7.5/10). Convex is the better pick for realtime TypeScript apps; Supabase for nearly everything else, because it's Postgres with auth, storage and vectors attached.

is Convex a Postgres database?

no. Convex is a document-relational database you query in TypeScript. its cloud runs on PlanetScale using MySQL for persistence, and the open source version can use SQLite, Postgres or MySQL underneath. you don't write SQL against it either way.

Convex vs Supabase pricing: which is cheaper?

both have a free plan. Supabase Pro is from $25 a month per organisation (with $10 of compute credit; each extra project adds compute). Convex Professional is $25 per developer a month. so for a solo dev the entry price is the same; for a team, Convex charges per developer and Supabase per project and usage.

can i self-host Supabase or Convex?

yes, both. Supabase self-hosts with Docker or the Supabase CLI (Apache 2.0). Convex has an open source backend you can self-host and develop against locally, under FSL-1.1-Apache-2.0.

does Supabase do realtime like Convex?

it has realtime (Postgres changes on every plan), with 200 concurrent connections on free and 500 on Pro. the difference is that in Convex every query is live by default; in Supabase you subscribe to the changes you want.

sources

checked 2026-10-26

• Supabase pricing (Free, Pro from $25 with $10 compute credit, Team from $599, pausing after 1 week, 2 free projects, MAUs, realtime connections, spend caps, self-hosting): https://supabase.com/pricing
• Supabase ai and vectors docs (pgvector, semantic, keyword and hybrid search): https://supabase.com/docs/guides/ai
• Supabase licence (Apache 2.0): https://github.com/supabase/supabase
• Convex pricing (Free and Starter $0 then pay as you go, Convex Professional $25 per developer a month, Business and Enterprise $2,500 monthly minimum, included resources, vector and text search): https://www.convex.dev/pricing
• Convex overview docs (reactive database, TypeScript queries, mutations as transactions, actions, scheduler, WebSocket clients, PlanetScale MySQL persistence, open source storage options): https://docs.convex.dev/understanding/
• Convex backend licence (FSL-1.1-Apache-2.0): https://github.com/get-convex/convex-backend
• ranks, scores, verdicts and plans: numptr data/tools.json (backend, database and deploy board)