Login, sessions and identity for your app.
An open-source authentication library for JavaScript apps, formerly NextAuth.js, supporting OAuth, email, and credentials-based flows.
A hosted authentication and user-management platform offering prebuilt UI components alongside a generous free tier.
Google's managed authentication service supporting email, phone, and federated sign-in, integrated tightly with the rest of Firebase.
The authentication layer of Supabase, providing email, OAuth, and row-level-security-aware sessions on top of Postgres.
An enterprise-grade identity platform offering configurable login flows, SSO, and extensive compliance features for larger applications.
A lightweight, framework-agnostic reference for building your own session-based authentication, rather than a heavier auth-as-a-service platform.
An open-source identity and access management server with single sign-on, social login and standards-based protocols, self-hostable for full control over your auth stack.
Enterprise-readiness APIs for SaaS apps — SSO (SAML/OIDC), SCIM directory sync and audit logs that plug into an existing auth setup instead of replacing it, aimed at teams selling to enterprise customers.
An open-source identity and access-management stack (Kratos for identity, Hydra for OAuth2/OIDC, Keto for permissions) that can be self-hosted or used as a managed cloud service.