Keycloak vs Zitadel
Self-host pick — both replace Auth0 (Identity / SSO / authentication-as-a-service).
Both Keycloak and Zitadel self-host as a replacement for Auth0 (Identity / SSO / authentication-as-a-service). Pick Keycloak if you want b2B apps that want SAML + OIDC + LDAP federation in one server, and don't mind Java footprint; pick Zitadel if you want multi-tenant SaaS that wants per-tenant orgs as a first-class concept. Both are Apache-family licensed and similar to set up.
| Keycloakopen-source | Zitadelopen-source | |
|---|---|---|
| License | Apache-2.0 | Apache-2.0 |
| Setup time | 20-30min docker-compose (Keycloak + Postgres) | 20min docker-compose |
| Monthly cost | $10 VPS for a small team; $20+ for production with HA Postgres. | $10-15 VPS — Go binary + CockroachDB or Postgres. |
| GitHub | keycloak/keycloak | zitadel/zitadel |
| Replaces | Auth0 | Auth0 |
Good fit for
Keycloak
B2B apps that want SAML + OIDC + LDAP federation in one server, and don't mind Java footprint.
Weak at:Java-heavy; theming and UX out of the box are dated vs Auth0.
Zitadel
Multi-tenant SaaS that wants per-tenant orgs as a first-class concept.
Weak at:Younger ecosystem; fewer tutorial articles than Keycloak.
In a terminal? npx -y github:SolvoHQ/os-alt-cli auth0 prints Auth0's self-host options including both —
how the CLI works →
FAQ
Which is easier to self-host, Keycloak or Zitadel?
Keycloak: 20-30min docker-compose (Keycloak + Postgres). Zitadel: 20min docker-compose.
What does each cost to run?
Keycloak: $10 VPS for a small team; $20+ for production with HA Postgres.. Zitadel: $10-15 VPS — Go binary + CockroachDB or Postgres.. Both projects are free and open source.
Do Keycloak and Zitadel replace the same SaaS?
Yes — both are open-source alternatives to Auth0.