BYD TechThe short answer
Supabase and Firebase both give a startup a ready-made backend: a database, sign-in, file storage and server functions. The main difference is the database. Supabase is built on PostgreSQL, a relational SQL database, and is open source, so it can be self-hosted. Firebase is Google’s platform, built around Firestore, a document database. Choose Supabase when your data has relationships and you value SQL and portability. Choose Firebase for real-time, mobile-first apps that fit its model.
Key points
- Supabase: PostgreSQL, SQL, open source, can be self-hosted.
- Firebase: Firestore document database, deep Google and mobile integration.
- Relational data, such as orders, customers and invoices, fits SQL naturally.
- Portability is easier from Postgres than from a proprietary database.
- Both handle sign-in, storage and functions well enough for a first version.
Side by side
| Supabase | Firebase | |
|---|---|---|
| Database | PostgreSQL, relational | Firestore, document-based |
| Query language | SQL | Firestore queries in the SDK |
| Open source | Yes, can be self-hosted | No, Google-hosted |
| Access rules | Row-level security in the database | Security rules |
| Real-time | Supported | A core strength |
| Ecosystem | Postgres tools and extensions | Google Cloud, Analytics, Crashlytics, messaging |
Firebase has also added a PostgreSQL-based option, Firebase Data Connect, for teams that want SQL inside Firebase.
The database is the real decision
Most business data is relational: a customer has orders, an order has items, an item belongs to a product. SQL databases model that directly, and questions like "which customers ordered this product last month" are a single query. Document databases store each record as a self-contained document, which is fast and flexible for some shapes of data and awkward for others.
- Many connected records and reporting needs: Postgres is the natural fit.
- Simple records read and updated in real time across devices: Firestore fits well.
- Unsure: relational is the safer default, because most products grow toward it.
Lock-in and portability
Supabase is open source and its database is standard PostgreSQL, so data and much of the setup can move to any Postgres host. Firestore is specific to Google, so leaving means reshaping the data and rewriting the code that reads it. For a first version this may not matter. For a company it often does.
How to choose
- Sketch your main data: what are the things, and how do they connect?
- If there are many connections, start with Supabase or another Postgres setup.
- If it is a mobile app with real-time sync and simple data, Firebase is strong.
- Check sign-in methods, region for data storage, and costs at your expected usage.
- Keep the accounts in your company’s name either way.
Supabase and PostgreSQL are what our MVP development page lists for ready-made sign-in, database and file storage. How a stack fits together is in What is a tech stack?.
Sources
Checked when this guide was written.
