Passwords

Password breach checker

Check whether a password appears in known data breaches. The password is never sent: your browser computes its hash and transmits only a fragment using k-anonymity.

Responsible use

Use these tools only on domains, addresses or credentials you own or are expressly authorised to assess. Their use is the sole responsibility of the person using them.

How it works

Your browser computes the SHA-1 hash of the password, sends only the first five characters and compares the rest locally. The full password never leaves your device.

Your password is processed in the browser and is never sent to our servers or logged.