Clerk
The most comprehensive user management platform.
Founded in 2020 by Colin Sidoti and Braden Sidoti through Y Combinator, Clerk was built to make authentication a solved problem for developers. While Auth0 and Cognito handle authentication as enterprise middleware, Clerk was designed for modern developers building with React, Next.js, and other contemporary frameworks. Clerk's pre-built UI components, SDK integrations, and developer-friendly APIs allow teams to add complete user management — sign-up, sign-in, MFA, organizations, and user profiles — in minutes rather than weeks. The company raised $170 million in 2024 at a $1 billion valuation and has become the go-to authentication solution for the Next.js and Vercel ecosystem, used by hundreds of thousands of developers and thousands of production applications worldwide.
Active Founders
Colin Sidoti
Founder / CEO
Colin Sidoti is the co-founder and CEO of Clerk. He and his brother Braden built Clerk after experiencing the pain of implementing authentication correctly in multiple production applications and realizing that every team was rebuilding the same infrastructure from scratch. Colin's focus on developer experience and his deep understanding of the modern JavaScript ecosystem has made Clerk the most beloved authentication platform for developers building with Next.js, React, and the broader Vercel ecosystem.
Clerk