How the password generator works
The generator builds a pool from the character types you select, then picks each character at random using your browser's cryptographic random number generator. It uses rejection sampling, which throws away random values that would make some characters slightly more likely than others.
To make sure every selected type appears, it first picks one character from each type, fills the rest from the full pool, and then shuffles the result with a Fisher-Yates shuffle driven by the same secure randomness.
How to use the password generator
- 1Set the length with the slider or type a number between 8 and 64.
- 2Choose which character types to include, and turn on look-alike filtering if you need to type the password by hand.
- 3Copy the password into your password manager or the sign-up form. Use Regenerate for a new one.
Frequently asked questions
Are these passwords random enough?
Yes. Every character comes from your browser's cryptographic random number generator (crypto.getRandomValues), the same source browsers use for security features. The tool also avoids modulo bias, so every allowed character is equally likely.
Is the password stored or sent anywhere?
No. Passwords are generated on your device and exist only on this page. Nothing is saved, logged or sent to a server, and reloading the page discards them.
How long should my password be?
Longer is stronger. For accounts you care about, 16 characters or more with all four character types is a solid choice. If you use a password manager, there is little reason not to go to 20 or beyond.
What does the strength meter measure?
It estimates entropy in bits: the length multiplied by log2 of the number of possible characters. Each extra bit doubles the number of guesses an attacker would need. The estimate assumes the password stays random, so do not edit it into a pattern.
Why avoid look-alike characters?
Characters like I, l, 1, O, 0 and o are easy to confuse when you read a password aloud or type it from paper. Removing them makes the pool a little smaller, so the tool shows the slightly lower strength honestly.