Password Entropy Calculator
See how many bits of entropy your password has. All processing in your browser.
About Entropy
Higher entropy means the password is harder to guess by brute force. We estimate the character set from what you type (lowercase, uppercase, digits, symbols). Use a long, mixed password for important accounts.
Frequently Asked Questions
What is password entropy?
Entropy measures unpredictability. More bits mean more possible combinations and a stronger password. Each bit doubles the number of guesses an attacker would need.
How is it calculated?
We estimate the size of the character set used (e.g. lowercase only = 26, add uppercase, digits, symbols for more). Entropy ≈ length × log₂(charset size).
Is my password sent anywhere?
No. Calculation is done entirely in your browser. Your password never leaves your device.