Keycloak vs Stack Auth
Comparing two open source alternatives to Auth0 . Use the comparison below to decide which one fits your needs.
Keycloak
Apache-2.0Open-source identity and access management with SSO, OAuth2, OIDC, and SAML support for modern applications.
Stack Auth
AGPL-3.0Open-source authentication platform for Next.js and React, built as an alternative to Auth0 and Clerk.
Side-by-side comparison
| Keycloak | Stack Auth | |
|---|---|---|
| License | Apache-2.0 | AGPL-3.0 |
| Self-hostable | Yes | Yes |
| GitHub Stars | 36,135 | 6,844 |
| Forks | 8,777 | 522 |
| Open Issues | 3,118 | 71 |
| Last Commit | Aug 12, 2026 | Aug 12, 2026 |
| First Released | Jul 2, 2013 | Feb 28, 2024 |
| Categories | ||
| Tags |
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