SecureMint
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How to Check Password Breaches

Check whether a password has appeared in known data breaches. Thanks to k-anonymity, your full password never leaves your browser.

1

Open the Breach Check page

Open the SecureMint Breach Check page (/breach-check). No signup or login required.

2

Enter the password to check

Type the password you want to check. It is SHA-1 hashed in your browser, and only the first 5 characters of the hash are sent to the external API.

3

Click 'Check'

Press the button for an instant result. Your input is matched against the Have I Been Pwned database.

4

Review the result

'Not found' means safe for now. If it shows 'appeared N times', change the password immediately. Generate a strong replacement on the Password Generator page.

5

Understand the privacy design

With k-anonymity, only the hash prefix (e.g. 5BAA6) is sent to the API, which returns matching hashes. The final comparison happens in your browser β€” so neither your password nor its full hash ever leaves your device.

Tips

  • πŸ›‘οΈUses the Have I Been Pwned k-anonymity API β€” only the first 5 characters of the SHA-1 hash are sent
  • πŸ”Great for auditing whether you've reused the same password across services
  • πŸ”‘If a breach is found, change it immediately. Use the Password Generator for a strong replacement