Auth.js

Open-source auth for Next.js and other frameworks, formerly NextAuth.

Other products from Authentication

Supabase is an open source Firebase alternative based on PostgreSQL.

Better Auth is a modern authentication library for Next.js, React, and other frameworks with built-in security features.

Drop-in authentication with hosted components, orgs, and session management.

Authentication and billing primitives for SaaS, with a generous free tier.