Compare · Keycloak
Seamless Auth vs Keycloak
Keycloak and Seamless Auth are both open source (Apache-2.0) and meant to be self-hosted. Keycloak is a full identity and access management server. Seamless Auth is a passwordless-only auth server for your own applications that lets your app render its own sign-in screens.
Read the full comparisonChoose Keycloak if
- You need SAML, for your applications or for brokering to external identity providers.
- You need LDAP or Active Directory federation, or Kerberos.
- You need a standards-based OpenID Connect provider for many applications today.
- You need SCIM provisioning.
- You need passwords alongside passkeys, or many isolated realms with separate configuration.
- You want a mature, widely deployed project with a large extension surface.
Choose Seamless Auth if
- Passkeys are the primary sign-in method, not an addition to a password form.
- You want sign-in screens to live in your app’s code, not in server-side templates.
- You want a smaller runtime: one Node.js container plus Postgres, with the admin console in the same image.
- Your stack has a Seamless Auth adapter: Node.js, Python, Go or Rust, with React, Angular, Vue, Svelte or React Native on the front end.
- You do not need SAML, LDAP or SCIM.
At a glance
| Feature | Seamless Auth | Keycloak |
|---|---|---|
| License | Apache-2.0 | Apache-2.0 |
| Runtime | Node.js, one container (API plus admin console) | Java |
| Passwords | No, by design | Yes |
| SAML | No | Yes, SAML 2.0 |
| LDAP and Active Directory federation | No | Yes |
| Sign-in UI | Rendered in your app by the SDK, or fully custom | Server-rendered themes built from FreeMarker templates |
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 Keycloak detail with the date it was checked.
Seamless Auth vs Keycloak 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 →