Password Strength & Entropy Calculator

Evaluate password entropy (bits), estimate brute-force cracking time, and detect common dictionary vulnerability patterns.

How to Use Password Strength & Entropy Calculator

  1. Enter Password to Evaluate: Type a candidate password or passphrase into the secure evaluation input.
  2. Calculate Information Entropy: The engine evaluates character pool size, length, dictionary patterns, and zxcvbn strength metrics.
  3. View Estimated Crack Time: Review estimated cracking times against supercomputers, offline GPU clusters, and online rate-limited attackers.

Frequently Asked Questions

How many bits of password entropy are considered secure?

Passphrases with at least 60–80 bits of entropy are considered resistant to offline GPU dictionary attacks, while 128 bits matches symmetric encryption strength.