Password strength checker
Estimate how long a password would take to guess, with plain feedback on weak patterns. It runs on your device and uploads nothing.
Type a password to see an estimate of how many guesses it would take, and how long that could last against an online login and against a stolen database. The tool looks for the patterns attackers try first: common passwords, ordinary words, sequences, keyboard runs, repeats and dates.
How it works
- Type or paste a password. Use Show if you want to see what you typed.
- Read the rating, the estimated guesses and the time against an online and an offline attack.
- Follow the feedback: make it longer, prefer random words, and drop years and keyboard patterns.
What happens to your data
- The password is checked by code running on this page. It is not sent to Revault or anyone else.
- There is no breach lookup, because that would mean sending something about your password. The tool makes no request at all while you type.
- Nothing is saved. The password stays in the page until you clear it or close the tab.
Limits to know about
- It is an estimate. The tool knows common passwords, several thousand everyday words and the usual letter-for-symbol swaps, so a password built from rarer words or names can still score higher than a dedicated cracking program would give it.
- It cannot tell whether a password has leaked or is used somewhere else. Never reuse a password, however well it scores.
Frequently asked questions
Is it safe to type my real password here?
The check runs in your browser and the page makes no network requests while you type, so nothing is sent. Even so, a good habit is to test a new password of the same style rather than one you use today.
How are the crack times worked out?
The tool estimates how many guesses an attacker would need, then divides by a speed. Offline it assumes 10 billion guesses a second, like fast hardware against a poorly protected stolen database. Online it assumes 100 a second, like a login form with limits. Real speeds vary a lot.
Why is a longer password better than a complicated one?
Every extra character multiplies the number of possibilities, while swapping a for @ is a trick attackers already try. Four or five random words are easier to remember than a short jumble and can be much harder to guess.