Supabase and Firebase are both backend-as-a-service platforms that let you build apps without managing your own server infrastructure. Firebase has a decade-long head start; Supabase is the newer open-source alternative built on PostgreSQL. The right choice depends on your data model, your team’s SQL comfort, and how much vendor lock-in you’re willing to accept.

Quick verdict

Choose Firebase for mobile apps that need real-time sync and offline support. Choose Supabase if you want a relational database, SQL queries, and an open-source stack you can self-host.

Key differences

• Database type: Firebase uses Firestore (NoSQL/document). Supabase uses PostgreSQL (relational/SQL) — a major difference if your data has relationships.
• Querying: Supabase supports full SQL queries. Firebase’s querying is more limited and requires careful data modeling to avoid expensive reads.
• Open source: Supabase is fully open source and self-hostable. Firebase is Google-proprietary — migrating away is painful.
• Real-time: Firebase has had real-time sync for years and it’s battle-tested. Supabase also offers real-time subscriptions but Firebase’s is more mature for offline-first mobile apps.
• Ecosystem: Firebase has tighter integration with Google Cloud, Google Analytics, and AdMob. Supabase integrates well with modern web stacks (Next.js, Vercel, etc.).

When to use Supabase

• Your data is relational and you want proper SQL joins
• You’re building a web app with a modern JavaScript stack
• You want to avoid vendor lock-in or need self-hosting options
• Your team knows SQL and Postgres

When to use Firebase

• You’re building a mobile app that needs offline sync
• You want real-time collaborative features that are deeply battle-tested
• You’re already on Google Cloud and want tight ecosystem integration
• Your data is naturally document-shaped (user profiles, activity feeds)

Bottom line

Supabase is the better choice for most new web projects in 2025 — it’s more flexible, more open, and SQL is a widely understood skill. Firebase still has the edge for offline-first mobile apps and Google ecosystem integration. If you’re starting fresh and not building a mobile app, Supabase is the safer long-term bet.