Password Strength Checker

Test the strength of your password, calculate its entropy, and see how long a brute-force attack would take to crack it.

🔒 Security Notice: Your password is calculated client-side in your browser and is NEVER transmitted over the Internet.
Strength Score: Very Weak (0%)0 bits entropy
Online Attack (Throttled)
Instantly
Standard web login throttling
Offline GPU Attack (100B/sec)
Instantly
High-speed supercomputer cluster
Security Checklist
  • ✗ At least 8 characters
  • ✗ At least 12 characters (Recommended)
  • ✗ Includes lowercase letters (a-z)
  • ✗ Includes uppercase letters (A-Z)
  • ✗ Includes numbers (0-9)
  • ✗ Includes special characters (!@#$%...)
Need a strong password? Try our Password Generator →

What Makes a Password Strong?

A strong password has high information entropy. Length is the single most critical factor: increasing password length from 8 to 14 characters multiplies the number of brute-force combinations by billions, transforming a crack time of seconds into centuries. Combining lowercase letters, uppercase letters, digits, and special characters further maximizes resistance to automated dictionary attacks.

How Password Crack Time is Estimated

Modern cybercriminals utilize high-powered GPU cracking clusters that compute over 100 billion hash evaluations per second against stolen password databases. Our tool calculates the mathematical probability of guessing your exact character combination across both online web scenarios and offline brute-force attempts.