Compare · Firebase Authentication
Seamless Auth vs Firebase Authentication
Firebase Authentication is a Google-operated sign-in service, with more features behind the paid Identity Platform upgrade. Seamless Auth is an open source, passwordless-only auth server that you self-host or run on the managed service.
Read the full comparisonChoose Firebase Authentication if
- Your app is built on Firebase and uses its Security Rules.
- You need password sign-in or anonymous accounts.
- You need SAML or many isolated tenants, with the Identity Platform upgrade.
- You want to run custom code inside the sign-in flow with blocking functions.
- You want mobile and game SDKs and a drop-in UI from one vendor.
- You need a vendor’s compliance reports or an SLA, or want nothing to run yourself.
Choose Seamless Auth if
- You want passkeys as the primary sign-in method. The Firebase docs, as checked, list no passkey sign-in method.
- Users and sessions must stay inside your own boundary, or outside the United States.
- You want the auth server, adapters, SDKs, dashboard and CLI under Apache-2.0.
- You want MFA, an audit trail and organizations without a paid upgrade.
- You prefer not to pay per active user or per SMS.
- You want your user data in a database you can query.
At a glance
| Feature | Seamless Auth | Firebase Authentication |
|---|---|---|
| License | Apache-2.0 for the server, SDKs, dashboard and CLI | Proprietary Google service |
| Hosting | Self-host (Docker, Postgres) or Seamless Auth managed hosting | Operated by Google |
| Where user data lives | Your Postgres when self-hosted | Google, US data centers only |
| Passwords | No, by design | Yes |
| Anonymous accounts | No | Yes |
| SAML enterprise SSO | No | With Identity Platform |
Sources and the full table
The docs page has the full feature table, the architecture difference, when not to use Seamless Auth, and a source for every Firebase Authentication detail with the date it was checked.
Seamless Auth vs Firebase Authentication in the docs →What it costs
Prices change, so this site does not repeat them. Any published prices are in the docs comparison with their sources and dates, and the cost calculator puts Auth0 and Okta Customer Identity list prices next to the cost of running Seamless Auth yourself.
Open the cost calculator →