🔒 Secure Password Breach Checker

Check whether a password has appeared in known data breaches while keeping it on your device. Your password never leaves your browser. Only the first five characters of its SHA-1 hash are sent to the Have I Been Pwned range API using the k-Anonymity model.

Check a password safely

Result

How this protects your privacy

  • k-Anonymity query, only the first five characters of the hash prefix are shared.
  • Local hashing, the SHA-1 hash is calculated in your browser.
  • No full hash transmission, the complete hash and password remain on your device.
  • Transparent logic, the JavaScript file can be inspected for reassurance.
Important notice & Legal disclaimer This Secure Password Breach Checker is a client side educational tool. All hashing takes place in your browser and only a partial hash prefix is sent to the Have I Been Pwned range API endpoint. Neither your full hash nor your plaintext password are transmitted to CyberLife Coach or stored by this page. Results are based on third party breach data and are provided without warranty. A password that does not appear in breach records is not automatically safe and should still follow modern best practices such as unique passwords per site and the use of a reputable password manager. Do not enter work managed or shared passwords without approval from your organization’s security team.