Best FusionAuth Alternatives

Authentik is an open-source Identity Provider supporting SAML, OAuth2/OIDC, LDAP, RADIUS, and SCIM for self-hosted single sign-on. It provides customizable authentication flows, multi-factor authentication, user management, and proxy-based SSO for applications without native support. Positioned as a modern Keycloak alternative with 22K+ GitHub stars, free Open Source use, and paid Enterprise/Enterprise Plus plans.

Ory provides a suite of modular open-source identity components: Kratos for user management and authentication, Hydra for OAuth2 and OIDC, Oathkeeper for API gateway authorization, and Keto for fine-grained permission management. Used by OpenAI and other major organizations. API-first design with Go-based microservices that deploy independently or together as Ory Network cloud.