What is the easiest way to add login to a web app?

Clerk is the easiest way to add sign in, with ready-made login screens, Google and email sign in, and a free tier for thousands of monthly users. If you already use Supabase, Supabase Auth is included free. Better Auth is a free open source library if you want logins inside your own code with no outside service.

Sites last checked 15 Oct 2026. How we test