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 | 37,100 | 6,861 |
| Forks | 9,003 | 523 |
| Open Issues | 3,198 | 79 |
| Last Commit | Oct 2, 2026 | Oct 2, 2026 |
| First Released | Jul 2, 2013 | Feb 28, 2024 |
| Categories | ||
| Tags |
GitHub stars over time
GitHub stars over time
Keycloak37,100
Stack Auth
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