Supabase vs Firebase: which backend for your app?

Choose Supabase if your app's data is relational, like customers, orders, invoices and bookings that link to each other, or if you want standard SQL and the freedom to move your database elsewhere later. Choose Firebase if you're building a mobile-first app that leans on Google's ecosystem for push notifications, analytics and offline sync, and your data fits naturally into documents. Both handle login, storage and real-time updates, and both let a small team launch without running servers.

Our own website runs on Supabase, and we've built client apps on both. Here's how they differ in ways that affect your budget and your options later.

What each one gives you

Both are "backend as a service" platforms. Instead of building and hosting your own server, database and login system, you use theirs.

Supabase is built around PostgreSQL, one of the most trusted open-source databases. On top it adds user authentication, file storage, real-time updates, serverless functions and auto-generated APIs. It's open source, so you can self-host it if you ever need to.

Firebase is Google's platform. Its main database, Firestore, stores data as documents in collections, a NoSQL model. Around it sit authentication, storage, Cloud Functions, hosting, and tools mobile teams rely on: Cloud Messaging for push notifications, Crashlytics for crash reports, Remote Config and analytics. Google has also added a PostgreSQL option called Data Connect, though Firestore remains the core of most Firebase apps.

The database question matters most

This is the decision that's hardest to reverse.

Business data is usually relational. A customer has many orders, each order has many items, each item belongs to a product, and your reports need to join all of that. PostgreSQL handles this naturally. You write a query, and the database does the joining.

Firestore stores documents. It's fast and simple for reading a user's profile or a chat thread, but reports that combine data across collections need more work: duplicating data, maintaining counters, or exporting to another system for analysis. Many teams start happily on Firestore and feel the pain a year later when finance asks for a report.

If your app is mostly content, chat or user profiles, documents are fine. If it looks like a business system with transactions and reports, relational is usually the better fit.

A quick way to tell: write down the five reports your business will want in a year. "Revenue by product by month", "customers who haven't ordered in 90 days", "bookings per staff member". If most of them combine several kinds of data, you want a relational database.

Reporting also matters for the tools around your app. Accounting exports, BI dashboards and data warehouses all speak SQL natively, so PostgreSQL data flows into them with little effort.

Security and access rules

Both let your app talk to the database directly from the browser or phone, which is fast to build. That makes security rules essential, because they're the only thing between a curious user and everyone else's data.

Supabase uses PostgreSQL's row-level security, written as SQL policies. Firebase uses its own security rules language. Both work well when written carefully. Both are dangerous when skipped, and misconfigured rules are among the most common problems we find in apps built quickly, including many AI-generated ones. We cover that in the vibe coding rescue guide.

Pricing and lock-in

What you pay each month

Both have free tiers good enough for prototypes.

Supabase's paid plan starts at $25 a month per project and includes a generous amount of database space, storage and users, with usage charges beyond that. Costs tend to be predictable because they scale with database size and bandwidth.

Firebase's paid plan is pay as you go. Firestore charges per document read, write and delete. That's cheap for small apps, but a screen that reads hundreds of documents on every open, multiplied by thousands of users, can produce surprising bills. Careful data design keeps it under control.

For most small and mid-size business apps, either platform costs somewhere between nothing and a few hundred dollars a month. Set up billing alerts on day one with either provider, so a bug that loops through the database shows up as an email, not as a surprise invoice at the end of the month. The difference shows up at scale and depends heavily on how the app is built.

Moving later

Supabase is standard PostgreSQL underneath. If you outgrow it or want to move, you can export the database and run it anywhere PostgreSQL runs, which is almost everywhere.

Leaving Firebase is harder. Firestore's data model and security rules are specific to Google, so moving means reshaping data and rewriting parts of the app. That doesn't make Firebase a bad choice. It makes it a long-term commitment you should make on purpose.

Our recommendation

For business software, SaaS products, admin-heavy apps and anything with reporting, we usually recommend Supabase. SQL, relational data and an easy exit are worth a lot over the life of a product.

For mobile-first consumer apps that need strong offline behaviour, heavy use of push notifications and Google's mobile tooling, Firebase is a solid choice, and its crash reporting and messaging are excellent even when the main database lives elsewhere. Many apps mix them: Supabase for data, Firebase for push and crash reports.

We pick per project on our web and app builds and SaaS products, and we'll explain the choice in plain language before you commit.

Questions about Supabase and Firebase

Is Supabase a good Firebase alternative?

Yes, especially for apps with relational data or teams who prefer SQL. It covers the same core features: database, authentication, storage, real-time and functions. Firebase still leads on some mobile tooling like crash reporting and messaging.

Which is cheaper, Supabase or Firebase?

For small apps both are cheap or free. At scale, Supabase costs are usually more predictable, while Firebase costs depend on how many document reads your app makes. Good data design matters more than the platform.

Can Supabase handle a large app?

Yes. It runs on PostgreSQL, which powers very large systems. Performance at scale depends on database design, indexes and queries, the same as any PostgreSQL setup.

Can I switch from Firebase to Supabase later?

Yes, but it's a migration project: reshaping document data into tables, rewriting security rules, and updating the app's data code. It's much easier to choose carefully at the start.

Get a backend recommendation

Tell us about your app: the data it handles and the reports you'll need. We'll recommend a backend and give you a fixed price for the build.