Evaluate password strength and estimated crack time based on complexity.
Strength is estimated from entropy — the length multiplied by the base-2 log of the character pool size. More characters and more variety (upper, lower, digits, symbols) exponentially increase the number of possible passwords and the time to crack them.
Entropy
Entropy (bits) = password length × log₂(character pool size)
Estimated crack time
Crack time ≈ 2^entropy ÷ guesses per second
This is an educational estimate of theoretical strength and does not account for dictionary words, reuse, or breaches. Use a password manager for real accounts.
No. The check runs entirely in your browser; the password never leaves your device.
Entropy grows linearly with length but only logarithmically with pool size, so adding characters usually helps more than adding symbol variety. A long passphrase is often stronger and easier to remember.