Clerk

Keycloak Open Source Identity and Access Management. Free realm up to 1000 users, up to 10 SSO connections, leveraging Phase Two's Keycloak enhanced container which includes the Organization extension.

Hosted SSO. The free plan includes 25,000 MAUs, unlimited Social Connections, a custom domain, and more.

Open-source API key management and rate-limiting platform. Free for up to 100,000 requests per month and 100 active API keys, with full access to key creation, revocation, and rate-limiting capabilities.

A turnkey user and access management that works for you and supports multi-tenant (B2B) use cases. Free for up to 25,000 authenticated requests, with all security features (no paywall for OTP, Passwordless, Policies, and so on). ⬆️ Back to Top

Free user management and authentication for up to 1 Million MAUs. Support email + password, social auth, Magic Auth, MFA, and more.

Open source user authentication that natively integrates into your app - enabling you to get started quickly while controlling the user and developer experience. Free for up to 5000 MAUs.

An all-in-one platform that provides APIs and SDKs for authentication and fraud prevention. The free plan includes 10,000 monthly active users, unlimited organizations, 5 SSO or SCIM connections, and 1,000 M2M tokens.

Open-source authentication that doesn't suck. The most developer-friendly solution, getting you started in just five minutes. Self-hostable for free, or offers a managed SaaS version with 10k free Monthly Active Users.