Password Strength

Measure password entropy in bits, estimate cracking time, and flag weak patterns.

How to use

Type or paste a password and press Analyse. The report shows the character pool, the Shannon-style entropy of the raw password, an average-case brute-force estimate at ten billion guesses per second, and every weak pattern detected.

FAQ

Entropy is length times log2 of the pool size counted from the character classes the password actually uses, so adding a symbol to a lowercase-only password widens the pool a lot. The tool runs entirely in your browser, so the password is never transmitted.

Privacy: every calculation runs inside your browser. Your files and text never leave your device.