Supabase vs Firebase

Short version: both let you start for free and add a database and sign-in to your app without running a server. Supabase gives every project a full Postgres database, and its paid plan starts at $25 a month with a spend cap switched on. Firebase's main database, Firestore, stores documents instead of tables, and its paid plan is pay as you go. On Firebase's free plan, file storage and server functions aren't available at all.

Supabase's paid plans charge a flat monthly fee, plus extra for added projects and add-ons, and, if you turn the spend cap off, for usage past the quotas. Firebase has two plans: Spark, which is free and needs no payment method, and Blaze, which includes the same no-cost quotas and bills you for usage above them.

What you pay

Plan	Supabase	Firebase
Free	$0: 500 MB database, 50,000 monthly active users, 1 GB file storage, 5 GB egress, 2 active projects	Spark, $0 and no payment method: Firestore with 1 GiB stored, 50K reads and 20K writes a day
Paid	Pro, from $25/mo, with $10 of compute credits that cover one project on the smallest compute size	Blaze, pay as you go, with the Spark no-cost quotas included
Next tier	Team, from $599/mo, adds SOC 2 and SSO for the dashboard	No third plan. Firebase has only Spark and Blaze
Sign-in	50,000 monthly active users free, 100,000 on Pro	50,000 monthly active users at no cost with Identity Platform. Phone sign-in is billed per SMS on Blaze
File storage	1 GB free, 100 GB on Pro	Needs Blaze. Spark projects can't use Cloud Storage
Server functions	500,000 Edge Function calls included free	Needs Blaze, then 2M calls a month at no cost
Over the free limit	You're notified, then service restrictions apply if you keep going over	On Spark, that product shuts off for the rest of the month
Billing	Monthly. No official yearly plan	Pay as you go, billed through Google Cloud

Prices are in US dollars. Checked October 21, 2026. Supabase compute is billed per project, so each extra project adds its own compute cost, from $10 a month. Supabase's own example: a Pro organization with two small projects costs $35 a month. Sources: Supabase's pricing page (opens in a new tab), Supabase's billing FAQ (opens in a new tab), Firebase's pricing page (opens in a new tab) and Firebase's guide to its pricing plans (opens in a new tab).

On Supabase, extra projects add compute, and usage the spend cap covers is billed past the quotas only if you switch the cap off. Add-ons you turn on yourself, like custom domains or backup restore, are billed either way. On Firebase, a small app can cost nothing on Blaze while it stays inside the no-cost quotas, though Firebase notes Cloud Functions can still create charges. Busy apps pay per read, write, gigabyte and call.

Where Supabase wins

• A real SQL database. Every project gets a full Postgres database. You can query it with SQL and add Postgres extensions such as pgvector for embeddings.
• More on the free plan. File storage and server functions both work on Supabase Free. On Firebase you need Blaze, which means adding a billing account.
• A cap on usage charges. Pro has a spend cap on by default. Once you hit the quota for things like egress, storage or monthly active users, that usage stops until the next billing cycle instead of being charged. Compute isn't covered by the cap.
• You can host it yourself. Supabase says self-hosting is free, with Docker as the recommended setup.

Watch out for: free projects pause after a week of inactivity, and you can only have two active free projects. Self-hosting means you handle the servers, security updates, backups and uptime, and some features of the hosted platform, like branching and managed backups, aren't available.

Where Firebase wins

• You can start without a card. Spark needs no payment method, and eligible projects that upgrade to Blaze get $300 in free credit.
• A lot of free tools for mobile apps. Analytics, Crashlytics, Cloud Messaging for notifications, A/B Testing, App Distribution and Performance Monitoring cost nothing on either plan. Firebase says most sign-in options are free even with several million users.
• Built for apps that go offline. Firestore caches the data your app is using, so it can keep reading and writing without a connection and sync when it's back online. Firestore has SDKs for Apple, Android and web apps, plus Unity, C++ and more.

Watch out for: on Blaze, budget alerts warn you but don't stop charges. Spend caps that pause a service exist only for Cloud Functions, App Hosting, Firebase AI Logic and Extensions. If you want SQL on Google's side, the first Cloud SQL for PostgreSQL instance you create through Firebase gets a three-month no-cost trial, one per project, then starts at $9.37 a month.

Which one should you pick?

• You want SQL tables and relations: Supabase.
• You need file uploads or server code without adding a card: Supabase Free.
• You want a predictable monthly bill: Supabase Pro, with the spend cap left on.
• You're building a mobile app that needs offline sync, notifications and crash reports: Firebase.
• Your app is small and you'd rather pay per use than a flat fee: Firebase Blaze, with budget alerts set up.
• You want to run the backend on your own servers: Supabase, self-hosted.

Both have a free way in, so build the same small feature on each and keep the one that's easier to reason about. Our page on the best AI tools for database and auth also covers Neon for serverless Postgres and Clerk for drop-in sign-in. If you'd rather describe your app and let AI build it, see Lovable vs Bolt.new.