Clerk is the complete authentication and user management platform for modern web and mobile apps. Founded in 2020, Clerk has quickly become the developer-favorite alternative to rolling your own auth or using Auth0 — with first-class support for Next.js, React, and other modern frameworks.

Clerk handles the entire auth stack: sign-up, sign-in, MFA, social OAuth, session management, user profiles, and organizations — all as polished, embeddable UI components that just work out of the box, while still being fully customizable.

Key Features

• Drop-in <SignIn />, <SignUp />, and <UserProfile /> React components
• Authentication methods: email, password, magic links, OTP, passkeys, and biometrics
• Social OAuth — Google, GitHub, Apple, Twitter, Facebook, Microsoft, and 20+ more
• Multi-factor authentication (TOTP, SMS, email OTP)
• Organizations and teams with roles and permissions
• Next.js App Router and Middleware support, with Edge runtime compatibility
• Session management, JWT templates, and Backend SDKs

Clerk is free for up to 10,000 Monthly Active Users, with Pro plans starting at $25/month and usage-based pricing as you scale.