Has Your Password Been Leaked? Check Breaches Safely
Check if your password appears in known data breaches using Have-I-Been-Pwned k-anonymity. Only a 5-char hash prefix leaves your device — your password NEVER does. 100% private. Free.
More tools
All free, all private — everything runs in your browser.
Password Strength Checker
Check how strong your password really is with zxcvbn real-world scoring, an estimated crack-time, and plain-English tips. The password is NEVER transmitted. 100% in-browser. Free.
Password Generator
Generate strong, random passwords with configurable length and characters. Powered by WebCrypto, with live entropy shown. 100% in your browser — never transmitted. Free.
Passphrase Generator
Generate memorable 'correct-horse-battery-staple' passphrases from the EFF diceware wordlist. Choose your word count. Strong and easy to type. 100% in-browser. Free.
Pronounceable Password Generator
Generate passwords that are easy to read and say aloud but still strong, built from random syllables with WebCrypto. Easier to remember, hard to crack. 100% in-browser. Free.
PIN Generator
Generate random numeric PINs from 4 to 8 digits for banking, phone, and SIM cards, with WebCrypto randomness. No patterns, no repeats. 100% in-browser. Free.
Bulk Password Generator
Generate dozens or hundreds of strong passwords at once with WebCrypto, then export the batch as CSV, JSON, or .zip. All in your browser — nothing is ever transmitted. Free + Pro.
How to use Password Breach Checker
- 1Type or paste a password to check. Your browser SHA-1 hashes it locally.
- 2Only the first 5 hex characters of the hash are sent to the Have-I-Been-Pwned API.
- 3Your browser receives hundreds of matching suffixes and checks for a match locally.
- 4See instantly whether the password appears in known breaches — the full password never left your device.
Password Breach Checker FAQ
- How can this be safe if it checks a remote database?
- It uses k-anonymity. Your browser SHA-1 hashes the password, then sends ONLY the first 5 hex characters of that hash to the Have-I-Been-Pwned API. The API returns every leaked suffix that shares that prefix (hundreds of them), and your browser checks the match locally. The full password — or its full hash — never leaves your device.
- What should I do if my password was found in a breach?
- Change it everywhere you used it, and never reuse it again. Generate a fresh, strong password here, and store it in a password manager so each account has its own unique password.