Security & Cryptography100% In-Browser CSPRNG (Zero Network Transmission)

Random Password Generator

Create strong, uncrackable passwords and memorable passphrases with customized character pools, length controls, entropy calculations, and crack-time assessments.

Password Length (16 characters):

Lowercase Lettersa-z

Uppercase LettersA-Z

Numbers0-9

Special Symbols!@#$%^&*()_+-=

Exclude Ambiguous CharactersAvoids i, I, l, 1, L, |, o, 0, O

Exclude BracketsAvoids <>()[]{}

Generate Quantity:

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What is Password Entropy and How is Strength Calculated?

Password entropy measures the unpredictability and information density of a password in bits. The mathematical formula is:

Entropy (H) = Length × log₂(Character Pool Size)

For example, a 16-character password using lowercase, uppercase, numbers, and symbols has a pool size of 94 possible characters:
16 × log₂(94) = 16 × 6.55 = 104.8 bits of entropy (virtually uncrackable by modern supercomputers).