Password Leak Check

// Password Leak Check

Your password never leaves your browser. We only send an encrypted fingerprint (hash) to our server — your actual password is never transmitted or stored.

How Password Data Breaches Work

Every year, billions of login credentials are stolen from websites and services in data breaches. Attackers compile these stolen passwords into massive databases used for credential stuffing — automated attacks that try leaked passwords across thousands of websites. If you reuse a password that appeared in any breach, every account using that password is at risk.

Our Password Leak Check lets you test whether a password exists in known breach databases. We maintain a local copy of over one billion compromised password hashes, updated weekly, so your check never depends on a third-party service.

How We Check Your Password Safely

Your password never leaves your browser. When you type a password, your browser computes a one-way cryptographic fingerprint (SHA-1 hash) of it locally. Only this irreversible hash is sent to our server, where it is compared against our database of known breached password hashes. Your actual password is never transmitted, stored, or logged — not even temporarily.

FAQ

How does the password leak check work?

Your browser converts your password into a cryptographic hash (a one-way fingerprint) before sending anything to our server. We compare this hash against a database of over one billion known breached password hashes. The process is entirely automated and your password is never stored.

Is it safe to enter my password here?

Yes. Your actual password never leaves your browser. We only receive an irreversible cryptographic hash — there is no way to reconstruct your password from this hash. Our server never sees, stores, or logs your password.

What should I do if my password was found in a breach?

Change that password immediately on every service where you use it. Use a unique, strong password for each account — a password manager makes this practical. Enable two-factor authentication wherever possible for an extra layer of protection.

How often is the breach database updated?

Our database is updated weekly with the latest known breached credentials from the Have I Been Pwned project, which aggregates data from publicly disclosed breaches worldwide.

Can a safe result guarantee my password has never been leaked?

A safe result means your password was not found in our current database of known breaches. However, new breaches occur regularly and some breaches are never publicly disclosed. Use strong, unique passwords regardless of the check result.