Password Strength Tester
Estimate a password's entropy and how long it would take to crack.
About this tool
A password's real strength comes from how unpredictable it is — measured in bits of entropy — which depends on its length and the variety of characters it draws from. This tester estimates that and translates it into an approximate crack time.
Type a password to see a live strength rating, its entropy in bits and how long a fast offline attack might take to guess it. Everything is calculated in your browser, so the password you enter never leaves your device.
Frequently asked questions
The analysis runs entirely in your browser — nothing is transmitted, logged or stored. That said, as a habit, avoid pasting passwords you actively use into any website.
Length above all, then variety. A long passphrase of random words beats a short string of mixed symbols. Aim for 16+ characters and never reuse passwords across accounts.
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