Password Entropy Explained
Entropy estimates how hard a password is to guess or brute-force.
Entropy basics
Entropy ≈ log₂(charsetlength)
More characters and broader character sets increase entropy. Length is usually the strongest factor.
Practical rule
Use at least 14–16 characters for important accounts, and never reuse passwords. A password manager helps maintain unique credentials.
Test and generate secure passwords
Use our Password Strength Checker to see entropy and generate stronger passwords.