UWTools
Security Tools

Password Entropy Calculator

Estimate theoretical password entropy locally in your browser.

0Estimated bits
0Character pool
Very lowRating
Enter a password to estimate theoretical entropy.

Calculated locally. This is a theoretical estimate, not a breach check.

Entropy estimate

The estimate uses length × log2(character pool size) based on the character classes present in the password.

Real-world strength differs

Human-generated passwords often contain patterns and reused words, so actual resistance to guessing may be lower than the theoretical value.