Supabase vs Firebase vs ShipStack: Which Backend Should You Choose in 2025?

Every app needs a backend. The question is how you get one.

Firebase is Google's all-in-one platform. It offers real-time databases (Firestore and Realtime Database), authentication, cloud storage, hosting, serverless functions, and analytics. It's mature, well-documented, and deeply integrated with the Google Cloud ecosystem. The trade-off is that Firebase uses proprietary APIs and a NoSQL data model that can be limiting for relational data.

Supabase positions itself as the open-source Firebase alternative. It's built on PostgreSQL, which means you get a full relational database with SQL support, row-level security, and real-time subscriptions. Supabase also provides auth, storage, and edge functions. The trade-off is that it's newer than Firebase and some features are still maturing.

ShipStack takes a different approach entirely. It's not a database provider or an auth service — it's a BaaS aggregator. ShipStack provides a single REST API that routes your requests to Supabase, Firebase, or Upstash behind the scenes. You get the speed of BaaS without locking into any single provider.

Firebase Auth supports email/password, phone, Google, Facebook, Apple, Twitter, GitHub, and anonymous sign-in. It has a mature SDK with built-in UI components for web and mobile. Firebase Auth is arguably the most battle-tested auth solution in the BaaS space.

Supabase Auth (GoTrue) supports email/password, magic links, phone OTP, and social providers (Google, GitHub, Discord, etc.). It integrates tightly with PostgreSQL's row-level security, so you can write database access policies that reference the authenticated user. This is powerful but requires learning Supabase's RLS syntax.

ShipStack Auth wraps both Firebase Auth and Supabase Auth behind a single endpoint: POST /api/auth/register, POST /api/auth/login, POST /api/auth/logout. The request and response format is identical regardless of which provider is behind it. This means you can start with Supabase Auth and switch to Firebase Auth later without changing your frontend code. The trade-off is that you're limited to the auth features ShipStack exposes — advanced provider-specific features may not be available through the unified API.

Firebase Firestore is a NoSQL document database. Data is stored as documents in collections. It scales automatically, supports real-time listeners, and has offline persistence built in. However, complex queries (joins, aggregations) are limited compared to SQL databases.

Supabase Database is PostgreSQL. You get full SQL, foreign keys, joins, views, functions, triggers, and extensions like PostGIS for geospatial data. Supabase also provides a REST API (PostgREST) and a real-time engine. If you need relational data modeling, Supabase is the clear winner.

ShipStack Database provides a unified CRUD API: POST /api/db/:table for inserts, GET /api/db/:table for queries with filters and pagination, PUT /api/db/:table/:id for updates, and DELETE /api/db/:table/:id for deletes. It works with both Firestore and PostgreSQL. You don't write raw SQL or Firestore queries — you send JSON and get JSON back. The trade-off is the same as auth: advanced database features (transactions, real-time subscriptions, stored procedures) may require direct provider access.

Firebase has a generous free tier (Spark Plan) but costs can escalate quickly on the Blaze (pay-as-you-go) plan, especially with Firestore reads and Cloud Functions invocations. Many developers have reported surprise bills when their apps go viral.

Supabase offers a free tier with 500MB database storage, 1GB file storage, and 50K monthly active users. The Pro plan starts at $25/month per project. Pricing is more predictable than Firebase, but you pay per project.

ShipStack is free for 1 project with 5,000 API calls/month. The Launch plan ($19/mo) gives you 3 projects and 100K calls. The Scale plan ($49/mo) offers unlimited projects with 1M calls. Importantly, ShipStack doesn't markup your provider costs — you pay your provider (Supabase, Firebase, Upstash) directly at their standard rates. ShipStack only charges for the API layer, rate limiting, analytics, and multi-tenant management.

Choose Firebase if you want a mature, all-in-one platform with excellent mobile SDKs, you're building a real-time app, and you're comfortable with NoSQL and the Google ecosystem.

Choose Supabase if you need a relational database (PostgreSQL), want an open-source solution, value SQL and row-level security, and prefer a more developer-centric approach.

Choose ShipStack if you want provider flexibility, you're building a multi-tenant application, you want to avoid vendor lock-in, or you're an agency managing multiple client projects with different provider requirements. ShipStack is also ideal if you haven't decided between Supabase and Firebase yet — start building and choose later.

The best part? With ShipStack, the choice isn't permanent. Start with Supabase, realize you need Firebase's real-time features for a specific project, and switch without rewriting a single line of frontend code.