Password Strength Checker
Entropy, estimated crack time, and specific tips to improve it.
Check a password's strength using entropy estimation and a common-password check, with an estimated brute-force crack time and specific suggestions to improve it — nothing is sent anywhere.
Frequently asked questions
Is my password sent anywhere?
No — everything is checked entirely in your browser using JavaScript. Nothing you type here is transmitted, logged, or stored anywhere.
What is entropy?
A measure (in bits) of how unpredictable a password is, based on its length and the variety of character types used. Higher entropy means more possible combinations an attacker would have to try.
How is crack time estimated?
It's a rough estimate assuming an offline brute-force attack at a fast guessing rate — real-world crack time varies a lot based on how the password is stored and the attacker's resources, so treat this as a relative comparison, not an exact prediction.