Password Generator

The Password Generator creates strong, random passwords using your browser's secure random number source, with full control over length and character types.

How passwords are generated

Each character is chosen independently and uniformly at random from your selected character sets (uppercase, lowercase, numbers, symbols) using crypto.getRandomValues, a cryptographically secure random source — not the predictable Math.random().

What is entropy?

Entropy measures password strength in bits, calculated as:

Entropy = length × log₂(pool size)

Higher entropy means more possible combinations an attacker would need to try. As a rough guide, 60+ bits is strong for most personal accounts, and 80+ bits is excellent for sensitive accounts.

Example: A 16-character password using all four character types (upper, lower, numbers, symbols — a pool of 94 characters) has about 105 bits of entropy, extremely resistant to brute-force attacks.

Privacy

Passwords are generated entirely in your browser and never transmitted anywhere. For network-related calculations, see our Subnet Calculator.

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