Handitab

Password Strength Checker

Check how strong a password is from its length and character variety, with an entropy estimate in bits and suggestions to improve it.

About Password Strength Checker

Password strength is an estimate of how hard a password is to guess. This checker multiplies the length by the base-2 logarithm of the character pool (26 lowercase, 26 uppercase, 10 digits, 32 symbols) to get entropy in bits, and caps the score at 20 bits for repeated characters, short all-digit strings, and well-known passwords. It has no dictionary or breach list. The password is checked in your browser and not sent anywhere.

How to use Password Strength Checker

  1. Fill in "Password to check".
  2. The result appears below and updates as you type.
  3. Copy the result with the copy button, or download it as a file where that is offered.

Questions about Password Strength Checker

Why is a long phrase of common words rated strong?

The estimate assumes every character is random. A phrase built from dictionary words is far easier to guess than its length suggests, and this checker has no word list, so treat high scores for readable phrases with caution.

Runs in your browser. Page last updated .

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