Thunder Tools

Password Generator

This free password generator creates strong, random passwords using your browser's cryptographically secure random number generator. Choose the length and which character types to include, and get a fresh password instantly — nothing is ever sent to a server.

Strength: Very strong
16

How it works

Adjust the length slider and toggle which character types to include — lowercase letters, uppercase letters, numbers, and symbols. A new password is generated instantly using your browser's `crypto.getRandomValues` API, a cryptographically secure source of randomness, so it's never predictable.

Tip

For most accounts, aim for at least 16 characters and enable all four character types. Longer passwords with more variety are dramatically harder to crack.

Is my password sent anywhere?

No. Everything happens locally in your browser — the password is generated on your device and never transmitted or stored anywhere.

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