EmbedAuth vs Supabase Auth: An Honest Comparison
A fair comparison of EmbedAuth and Supabase Auth — bundled backend vs standalone embeddable auth, where each shines, and how to choose based on your stack and white-label needs.
Supabase Auth is part of Supabase, an open-source Firebase alternative that bundles a Postgres database, storage, realtime, and authentication into one platform. Comparing it to EmbedAuth is partly a comparison of philosophies: an all-in-one backend versus a focused, embeddable auth component. Here is a fair breakdown.
The one-line summary
- Supabase Auth is the authentication piece of the broader Supabase platform, tightly integrated with a Supabase Postgres database and its row-level-security model. It shines when Supabase is already your backend.
- EmbedAuth is a standalone, embeddable authentication product that drops into any stack via an iframe and returns a signed JWT, with per-customer white-label theming as a core goal.
Integration model
Supabase Auth is most powerful when you use the rest of Supabase. Auth issues JWTs that flow naturally into Postgres row-level security policies, so auth.uid() is available directly in your database rules. If Supabase is your database and backend, this integration is a genuine superpower — authorization lives right next to your data. The client libraries provide sign-in methods you call from your app code.
EmbedAuth is backend-agnostic. It does not assume anything about your database or hosting; it renders auth in an iframe and hands your server a standard RS256 JWT to verify however you like. That makes it a fit when your stack is not Supabase, when you want auth decoupled from your data layer, or when you need the same auth across several services.
Feature comparison
| Supabase Auth | EmbedAuth | |
|---|---|---|
| Positioning | Auth within a full backend platform | Standalone embeddable auth |
| Best-case synergy | Supabase Postgres + RLS | Any stack, any database |
| Integration | Client SDK + Supabase backend | Iframe + postMessage + JWT |
| UI | Bring-your-own or Auth UI helpers | Hosted, themeable embedded form |
| White-label per customer | Possible, manual | First-class design goal |
| Open source / self-host | Yes | Hosted product |
| Token format | JWT | JWT (RS256) |
| Best for | Teams already on Supabase | SaaS wanting embedded, portable auth |
Where Supabase Auth is the better choice
We would recommend Supabase Auth if:
- You are already building on Supabase — its Postgres, storage, and realtime — and want auth that plugs directly into row-level security.
- You value open source and self-hosting and want to run the whole stack yourself.
- You want a single vendor for database + auth + storage rather than composing separate services.
- Your authorization logic is naturally expressed as database RLS policies keyed on the authenticated user.
Where EmbedAuth is the better choice
EmbedAuth tends to win when:
- Your backend is not Supabase (custom API, a different database, or multiple services) and you want auth that doesn't assume a data layer.
- You need a hosted, themeable auth UI embedded on your page rather than assembling your own from primitives.
- You are building white-label SaaS where each customer's login must carry their branding.
- You want auth decoupled from your database so you can change either independently.
A note on authorization
The two products draw the auth/authz line differently. Supabase pulls authorization into the database via RLS — elegant when Supabase is your backend. EmbedAuth stops at authentication and hands you a verified identity, leaving authorization to your application layer. If you're designing multi-tenant authorization either way, the trade-offs (including where to enforce tenant_id and how to use RLS as a backstop) are covered in Designing Multi-Tenant Authentication.
Bottom line
If Supabase is your backend, Supabase Auth is the natural, well-integrated choice and its database synergy is hard to beat. If you want authentication that is independent of your data layer, embeddable on your own page, and built for white-label SaaS, EmbedAuth is the better fit. The deciding question is usually simple: is Supabase already your backend?
Related reading: OAuth 2.0 explained and JWT explained for developers.