Supabase vs Firebase: Which Backend Should You Choose?

Backend-as-a-Service (BaaS) platforms let you launch apps without building a backend from scratch. The two best-known are Firebase, from Google, and Supabase, an open-source alternative built on PostgreSQL. We use both — and recently migrated our own website's data to Supabase — so here's a practical comparison.

What do they provide?

Both platforms bundle the building blocks most apps need:

Feature	Firebase	Supabase
Main database	Firestore (NoSQL documents)	PostgreSQL (relational)
Authentication	Firebase Authentication	Supabase Auth
File storage	Cloud Storage for Firebase	Supabase Storage
Server functions	Cloud Functions	Edge Functions
Real-time updates	Built into Firestore	Realtime (database changes, broadcast, presence)
Security model	Security Rules	Postgres Row Level Security
Open source / self-hostable	No	Yes

The biggest difference: the database

Firebase's Firestore is a NoSQL document database. It's excellent for real-time sync and mobile apps, but relational queries — joins, complex filters and reports — can be awkward and may require duplicating data. Firebase has also introduced Data Connect, backed by Cloud SQL for PostgreSQL, for teams that want a relational option.

Supabase gives you a full PostgreSQL database. You get SQL, joins, foreign keys, transactions, views and extensions — and you can connect any standard Postgres tool. If your data is relational (customers, orders, bookings), this is a major advantage. Read more in PostgreSQL vs MongoDB.

Security

• Firebase Security Rules control who can read and write each document. They're powerful but have their own syntax that must be tested carefully.
• Supabase uses PostgreSQL Row Level Security (RLS) policies written in SQL. An important tip from experience: Supabase exposes tables in the public schema through its auto-generated API, so enable RLS on every table — otherwise anyone with your public key may be able to read them.

With either platform, misconfigured rules are the most common security mistake, so review them before launch.

Mobile and offline features

Firebase has a long track record on mobile. Its SDKs offer offline data persistence and integrate with other Google services such as Cloud Messaging for push notifications, Crashlytics and Analytics. If you're building a mobile-first app that must work offline, Firebase is very strong.

Pricing

Both have free tiers for prototypes.

• Firebase uses pay-as-you-go pricing on its Blaze plan, largely based on usage such as document reads and writes. Costs can climb if your app reads data inefficiently, so data modelling matters.
• Supabase uses plan-based pricing with included usage, plus charges for extra compute, storage and bandwidth. Costs are generally easy to predict for database-heavy apps.

Always model your expected usage before committing.

Lock-in and portability

Firestore's data model and APIs are specific to Google, so moving away later means rewriting data access code. Supabase is open source and built on standard PostgreSQL — you can export your database with standard tools or self-host the platform.

Which should you choose?

Choose Firebase if:

• you're building a mobile-first app with offline support and push notifications;
• your data is document-shaped and real-time sync is central;
• you're already invested in Google Cloud.

Choose Supabase if:

• your data is relational, or you need SQL reporting;
• you want open-source portability and standard Postgres tools;
• you're building a web app or SaaS with Next.js or React.

Build your MVP faster

We build MVPs and production apps on Firebase and Supabase — real-time features, authentication and properly configured security rules included. Explore our Firebase & Supabase service or contact us for advice on the right backend.