Supabase vs Firebase in 2026: which to build on, and what each costs in production

Supabase or Firebase: which should you choose?

Choose Supabase if you need

• Relational data: tables, joins and SQL you can take to any Postgres host.
• One access-control layer that applies to every client, written as database policies.
• A flat monthly plan with a spending cap.
• The option to self-host, since the whole platform is open source.
• To keep building on an app an AI builder generated. Lovable, for one, runs its apps on Supabase.

Choose Firebase if you need

• An offline-first mobile app. Firestore caches data on the device out of the box.
• Tight integration with Google Cloud and its identity and access management.
• Pay-per-use pricing that costs nothing when nobody is using the app.
• Postgres without leaving Firebase, through SQL Connect.

How do Supabase and Firebase compare?

Is Firebase still NoSQL only?

No. Firebase SQL Connect, launched as Data Connect in April 2025 and renamed in April 2026, is a fully managed PostgreSQL database on Google Cloud SQL. It is queried through GraphQL operations with generated, type-safe SDKs. The April 2026 release added realtime query updates, offline caching and native SQL. Most comparisons still describe Firebase as NoSQL only, and that is out of date.

Pricing is separate from Firestore: 250,000 operations a month free, then $0.90 per million, plus the Cloud SQL instance, which Google lists from $9.37 a month. Projects on the free Spark plan get a 90-day trial.

How do Supabase row-level security and Firebase Security Rules differ?

In Supabase, each policy is attached to a table and runs every time the table is accessed, whoever is asking. In Firebase, Security Rules match document paths and check conditions on Google’s servers for Firestore, Realtime Database and Storage. Both work, but both have a way around them:

• Supabase’s secret service_role key bypasses row-level security entirely, so it must never reach a browser or a mobile app.
• Firestore’s server client libraries bypass Security Rules and rely on Google Cloud permissions instead.

On existing Supabase projects, new tables in the public schema are open to signed-in and signed-out users until row-level security is switched on. Supabase says it is changing that default but hasn’t given a date. Our symptom-by-symptom guide to Supabase RLS covers the fixes.

What does Supabase cost in production?

The free plan is not built for production: projects pause after a week without activity, and there are no backups. A production app is on Pro, which Supabase lists “from $25 a month”. Here is what the rest of the bill depends on:

Supabase’s own worked example, Pro with Small compute, comes to $30 a month. Add point-in-time recovery, which lets you restore to any moment rather than last night’s backup, and a careful production setup is about $130 a month. The spend cap is on by default but does not cover compute or recovery add-ons.

What does Firebase cost in production?

Firebase has no monthly fee on the Blaze plan: you pay for what you use beyond a free daily allowance. Cloud Functions and Storage require Blaze. For Firestore’s standard edition, Google’s September 2026 prices are:

An illustration, not a measurement: an app doing 300,000 reads and 50,000 writes a day in us-central1 pays for 250,000 reads ($0.075) and 30,000 writes ($0.027), about $0.10 a day or $3 a month. Authentication is free up to 50,000 monthly active users, and Cloud Functions include 2 million calls a month, then $0.40 per million.

The risk is the other direction. A bug that reads the same documents in a loop is billed like real traffic, and Firebase budget alerts, by Google’s own description, do not cap usage or charges.

Which one do AI app builders use?

Many use Supabase. Lovable runs its apps on it, and Supabase said in June 2026 that more than 60% of new databases on its platform are launched by some kind of AI tool. That makes the security section above the one to read: a generated app is only as safe as the row-level security policies on its tables, and those are often incomplete. Our list of the 20 ways AI-built apps fail in production starts there.

Can you move from Firebase to Supabase, or back?

Yes, but it is a migration, not an export. Documents become tables, Security Rules become policies, and users move between two authentication systems. Getting data out of Firestore needs the Blaze plan, lands in a Cloud Storage bucket, and costs one read per document. Supabase data is a standard Postgres database, so it moves with standard Postgres tools.

What next?

If you are choosing, start from the list at the top of this page. If you already run on Supabase, and especially if an AI builder set it up, the AI-Built App Audit Report checks every table, policy, function and bucket with read-only access for $349. If you are starting fresh, we build web apps in about a week on whichever fits.