Clerk

About Clerk

Clerk is an authentication and user management platform for developers building web applications. It provides drop-in UI components—including sign-up, sign-in, user profile, and account switcher elements—that can be styled with any CSS library and deployed on a custom domain. The platform covers both individual user authentication and B2B use cases, with components for creating organizations, switching between accounts, and managing organization membership, invitations, and settings.

The product includes security features such as multifactor authentication, session management with active device monitoring and session revocation, bot detection powered by machine learning, and fraud/abuse prevention that blocks disposable email domains and restricts email subaddressing. Additional authentication options include social sign-on with 20+ providers, magic links, email and SMS one-time passcodes, and password-based authentication with breach detection. Clerk also offers API key management for issuing production-ready API keys to users without custom backend or UI work.

Clerk states it is SOC 2 Type 2 and CCPA compliant, with regular third-party audits and penetration testing. The platform also includes a billing feature that lets developers display pricing plans and subscription options to their end users through a component-based interface.

Key features

• Drop-in UI components for sign-up, sign-in, user profile, and organization management
• B2B organization management with switching, invitations, and membership roles
• Multifactor authentication enforced automatically during sign-in
• Fraud and bot detection with disposable email and abuse blocking
• Session management with active device monitoring and revocation
• Social sign-on with 20+ providers

Frequently asked questions