Password Breach Checker
Check if your password has been exposed in known data breaches using the HaveIBeenPwned API.
Your Privacy is Protected
We use the k-anonymity model to protect your password. Only the first 5 characters of your password's SHA-1 hash are sent to the API. Your full password never leaves your browser.
Ready to Check
Enter a password to check if it has been exposed in data breaches.
Breach Information
How It Works
1. Local Hashing
Your password is converted to a SHA-1 hash entirely within your browser.
2. k-Anonymity
Only the first 5 characters of the hash are sent to the API for matching.
3. Secure Comparison
The API returns hash suffixes that match your prefix for local comparison.
About Data Breaches
What is a Data Breach?
A data breach occurs when sensitive information is accessed, stolen, or used by unauthorized individuals. This often includes email addresses, passwords, and personal data.
Why Check Passwords?
If your password appears in breach databases, it's vulnerable to credential stuffing attacks where hackers try the same password on other services.
How to Protect Yourself
Use unique passwords for each service, enable two-factor authentication, and consider using a password manager to generate and store strong passwords.
About HaveIBeenPwned
This service uses Troy Hunt's HaveIBeenPwned API, which contains over 10 billion accounts compromised in data breaches.