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Password Generator

Generate a strong, random password with customizable length and character sets, along with an entropy-based strength estimate.

About the Password Generator

Generate a strong, random password with the exact length and character mix you choose, along with an estimate of how hard it would be to crack.

How the Password Generator works

Every character generated uses the browser's cryptographically secure random number source (crypto.getRandomValues), not Math.random(), so the output isn't predictable the way a pseudo-random generator can be. Password strength here is estimated using Shannon entropy: the character pool size raised to the power of the password length, expressed in bits — more available character types and more characters both increase entropy, and therefore how many attempts a brute-force search would need.

How to use the Password Generator

  1. Choose a password length.
  2. Toggle which character types to include: uppercase, lowercase, numbers, and symbols.
  3. Optionally exclude visually ambiguous characters (like 0/O or l/1).
  4. Press Generate to create a new password and see its estimated entropy and strength rating.

Tips for the Password Generator

  • Longer passwords are far more effective than complex short ones — a 16-character password beats a 8-character one with symbols.
  • Use a unique password for every account; a password manager makes this practical.

Formula used by the Password Generator

Entropy (bits) = length × log₂(character pool size)

Example: Password Generator

A 16-character password using all four character types

  • Length: 16
  • Character types: Uppercase, lowercase, numbers, symbols (88-character pool)

Result: Entropy ≈ 103.4 bits — "Very Strong"

Entropy = 16 × log₂(88) ≈ 16 × 6.46 ≈ 103.4 bits, well above the 80-bit threshold this tool labels "Very Strong."

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