If you're building a web app in 2025 and choosing a backend, the Supabase vs Firebase question comes up almost immediately. Both are Backend-as-a-Service platforms that handle auth, database, storage, and real-time data. Both integrate cleanly with Next.js and React.
But they're very different tools — and for most Australian developers and startups, one is the better choice.
The Short Answer
If you're building something serious in 2025 — especially with Next.js — use Supabase.
Here's why.
What Firebase Gets Right
Firebase, Google's BaaS platform, has been around since 2011. It's mature, battle-tested, and has a massive ecosystem. For certain use cases it's still excellent:
- Mobile apps (Firebase is deeply integrated with Android/iOS tooling)
- Real-time apps built around Firestore's document model
- Teams already deep in the Google Cloud ecosystem
Firebase is fast to prototype with and has great documentation.
Where Firebase Falls Short
The cracks show when you need to do anything that doesn't fit Firebase's model:
NoSQL at scale is harder than it looks. Firestore's document/collection model is intuitive at first, but complex relational queries — the kind you need in any real business app — become painful. You end up duplicating data, denormalising everything, and writing workarounds for things SQL handles in one line.
Vendor lock-in is real. Firebase is proprietary Google infrastructure. Your data is in their format, on their servers. Migrating out is not trivial.
Pricing surprises. Firebase's read/write pricing can spike unexpectedly under load. Australian teams have been burned by this — especially apps that do a lot of reads.
No SQL. Seriously. If your app evolves to need joins, foreign keys, or aggregate queries, you're working against the tool.
What Supabase Gets Right
Supabase is the open-source Firebase alternative built on PostgreSQL. It launched in 2020 and has grown aggressively — over 100,000 databases launched monthly as of 2025.
It's just Postgres. This is the big one. You get a real relational database with the full power of SQL. Joins, indexes, views, foreign keys, row-level security, triggers — all of it works exactly as you'd expect.
Auth is first-class. Supabase Auth handles email/password, magic links, OAuth (Google, GitHub, etc.), and phone OTP out of the box. It's clean to integrate and easy to extend.
Edge Functions for server-side logic. Run TypeScript functions close to your users without spinning up a full backend.
Open source and portable. You can self-host Supabase if you need to. Your data is in a standard Postgres database — you can always take it somewhere else.
Pricing is predictable. The free tier is generous, and paid plans are flat-rate per project. No surprise bills.
The Next.js Angle
Most Australian startups and agencies building web apps are on Next.js + Vercel. Supabase was built with this stack in mind.
The @supabase/ssr package handles server-side auth in the App Router cleanly. Row-level security policies let you enforce access control at the database level, so your API routes don't have to. The combination of Next.js + Supabase + Vercel is genuinely one of the most productive stacks available right now.
Practical Comparison
| Supabase | Firebase | |
|---|---|---|
| Database | PostgreSQL (relational) | Firestore (NoSQL) |
| Auth | Built-in, flexible | Built-in, mature |
| Pricing model | Flat-rate per project | Usage-based (reads/writes) |
| Open source | Yes | No |
| Self-hostable | Yes | No |
| SQL support | Full | No |
| Next.js integration | Excellent | Decent |
| Australian data residency | Configurable | Limited |
Data Residency for Australian Teams
One consideration Australian teams often overlook: where does your data actually live?
Supabase lets you choose your database region — including AWS ap-southeast-2 (Sydney). For apps handling Australian user data, keeping it in-country matters both for latency and for compliance considerations.
Firebase's Firestore has fewer regional options for Australian teams.
When to Still Use Firebase
- You're building a mobile-first app deeply tied to the Google ecosystem
- Your team already knows Firestore and the app doesn't need relational data
- You need Firebase's real-time listeners and your data model fits documents naturally
Conclusion
For Australian developers building web apps on Next.js in 2025, Supabase is the stronger choice in almost every scenario. The combination of PostgreSQL's power, predictable pricing, great Next.js support, and Australian data residency options makes it the practical pick for serious production apps.
If you're starting a new project or looking to migrate an existing app to a better stack, get in touch — I can scope out the backend setup and get it production-ready.