About

What is PW Checkup?

PW Checkup is a free tool for checking whether a password you use has appeared in a known data breach. No sign-up, no install — it runs entirely in your web browser.

Why is it free?

This service is built on the widely-trusted "Have I Been Pwned" Pwned Passwords database. We've added a privacy-safe k-anonymity lookup flow, clear bilingual explanations, and a trustworthy interface on top of it.

Your password is never transmitted

Every check happens inside your own browser. Your password is hashed with SHA-1 locally, and only the first 5 characters of that hash are sent for lookup. Your full password — and full hash — never reach any server. See our guides for the full technical explanation.

Who's behind this

PW Checkup is an independent, small-scale project focused on one thing: password security. If you have feedback or run into an issue, see our Contact page.