Both give you auth, database, and storage without managing servers. The developer experience diverges sharply.
Choose Supabase When
- You want real Postgres and SQL
- Row-level security fits your auth model
- You prefer open source and self-host option
- Your stack is already SQL-friendly
Choose Firebase When
- You need real-time sync out of the box
- You're building mobile-first (great SDKs)
- NoSQL document model fits your data
- You're deep in the Google Cloud ecosystem
I default to Supabase for web apps. I pick Firebase when real-time collaboration is the core feature.