Password security

See how long your password would really last.

Type a password and get a plain-english read on its strength, the math behind it, and how long it would take an attacker to crack. Nothing leaves your browser.

About password entropy

What it measures

Entropy is a measure of how unpredictable a password is, expressed in bits. More bits means more guessing before someone gets it right.

How it's calculated

Entropy = length × log₂(pool size). The pool is how many distinct characters you could have used; length is how many you did.

Why it matters

Higher entropy means exponentially more combinations to try, which is what pushes crack times from seconds into centuries.

01

Enter a password

Everything is calculated on your device. The password never touches a server.

Or try an example

03

Model a specific attacker

Optional. Pick the hardware and hashing an attacker might use to see a tailored crack time.