What should I do if my password is found in a breach?

Treat it as compromised and change it everywhere you used it. Create a long, unique password for every site and enable two-factor authentication. The easiest way to manage this is a password manager.

Security

Password leak check

Q: Can you see my password?

No. The password is hashed right in your browser with SHA-1, and only the first 5 characters of the hash are sent to the server. Hundreds of possible hashes match that prefix, so your exact password can never be identified. This is called k-anonymity.

Q: Is it free and without sign-up?

Yes. The check is completely free, requires no account and stores nothing — no passwords, no history. Check as many passwords as you like.

Find out whether your password has appeared in a known data breach. Your password never leaves the browser: it is hashed locally, and only the first five characters of the hash are sent (k-anonymity). Free and no sign-up.

Use the tool Free tools

No sign-upProcessed locallyFree forever

k-anonymity · SHA-1Runs in your browser

Breach check

Only the first 5 characters of the password hash leave your device.

This checks one password. To watch the site itself — more than one monitor and a check that the sign-in page still contains the phrase it should — that is a paid Astrina plan. Uptime for one address and TLS-expiry alerts are free there. See the plans

The password is hashed on your device; only the first 5 characters of its SHA-1 hash are sent. We never see or store the password.

How it works

Privacy comes from how the check is built, not from a promise.

Stays in your browser

The password is hashed locally with SHA-1. The plain password is never sent to us or anyone else.

k-anonymity

Only the first 5 characters of the hash are queried — hundreds of values match that prefix, so your exact password is never revealed.

Nothing is stored

No logs, no accounts, no history. Check as many passwords as you like.

Frequently asked questions

FAQ

Didn’t find your answer?

Ask us directly

Can you see my password?

No. The password is hashed right in your browser, and only the first 5 characters of the hash are sent. Hundreds of possible hashes match that prefix, so your exact password can never be identified.

Where does the breach data come from?

From the Pwned Passwords database by Have I Been Pwned — hundreds of millions of passwords from real breaches. The tool checks your password hash against it without revealing the password.

If my password is not found, is it safe?

Not necessarily. Not appearing in known breaches is a good sign, but new breaches happen constantly and a short password can be guessed without one. Always use long, unique passwords.

Is it free and without sign-up?

Yes. The check is free, requires no account and stores nothing.

Keep going

More free tools

Free tools

Password generatorCreate a long, unique password of any length — cryptographically strong, right in your browser.QR code generatorA QR for any link or text with PNG download — no watermarks, right in your browser.UTM link builderBuild links with utm_source, utm_medium and utm_campaign. Presets for Google Ads, social and email.URL slug generatorTransliterate Russian and Ukrainian text into a clean, SEO-friendly URL slug.Character counterCharacters, words, sentences and reading time — with limits for SEO, X/Twitter and Telegram.Phone number checkE.164 format, country by code and validity — in the browser. Carrier and spam-risk are paid Astrina.

Ostohlo studio

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