Security & Encoding
Security Tools Browser Only

Free Password Strength Checker Online

Evaluate password strength using the zxcvbn algorithm. Entropy, crack time, and feedback — all in your browser.

Type a password above to see its strength

Password is evaluated locally using zxcvbn. It never leaves your browser.

Frequently Asked Questions

Is this password strength checker free?+
Yes, free with no sign-up. The entire evaluation runs in your browser using the zxcvbn library.
Does my password get sent anywhere?+
No. The password is evaluated entirely in your browser. No network request is made. Your password never leaves your device.
What is entropy in a password?+
Entropy measures the randomness of a password in bits. Higher entropy means more possible combinations an attacker would need to try. A password with 50+ bits of entropy is considered strong for most purposes.

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