Secure Password Generator — Strong Random Passwords Free
Generate strong, secure random passwords free — cryptographically secure using your browser's built-in random number generator. Customize length, include/exclude symbols, numbers and ambiguous characters.
Last updated: June 2026
Character sets
Passwords are generated locally with crypto.getRandomValues() — never transmitted or stored.
About this tool
How to generate a strong, secure password
A strong password is long and unpredictable, drawn from a large mix of character types so it
can't be guessed or brute-forced. The single most important factor is true randomness, and that's
where most generators fall short. This
password generator uses the browser's
crypto.getRandomValues() — a cryptographically secure random source — rather than the
predictable Math.random(), so every password is genuinely unguessable.
Choose a length (16 or more is a sensible default, and longer is always stronger), then pick your character sets: uppercase, lowercase, numbers and symbols, plus the option to exclude ambiguous characters like 0 and O when a password will be typed by hand. You can add your own custom characters and generate up to ten passwords at once, each with a copy button and a strength meter that shows the estimated entropy in bits.
Crucially, nothing is sent anywhere. Every password is created on your device and exists only until you copy it — there's no server, no logging, and no storage. For the safest workflow, generate a long random password here and paste it straight into your password manager. It's free, private, and unlimited.
How it works
Three quick steps — no account, nothing uploaded to a server.
Enter your input
Paste or type your data into the tool.
Generate a password
Choose length and character types for a strong password.
Copy or download
Copy the result to your clipboard or download it as a file.
FAQ
Frequently asked questions
Are these passwords safe to use?
Yes. Passwords are generated locally in your browser using crypto.getRandomValues(), the same cryptographically secure random source recommended for security-sensitive work — not the predictable Math.random(). Nothing is transmitted, logged or stored on any server, so the password exists only on your device until you copy it. For maximum safety, paste it straight into a password manager.
How long should a password be?
Longer is stronger. Aim for at least 16 characters for important accounts; 20 or more is better for anything critical. Length matters more than complexity, because each extra character multiplies the number of possible combinations an attacker must try. The tool shows the estimated entropy in bits so you can see how strong each password is — over 100 bits is very strong.
What does 'exclude ambiguous characters' do?
It removes characters that are easy to confuse when read or typed by hand — like 0 and O, or l, 1 and I. This is useful when a password will be typed manually or read aloud. If the password only ever lives in a password manager, you can leave ambiguous characters in for slightly more entropy.
How is password strength calculated?
Strength is based on entropy: the length multiplied by the log-base-2 of the size of the character pool you've enabled. A longer password drawn from a bigger mix of character types has more entropy and is exponentially harder to crack by brute force. The meter maps the estimated bits to labels from Very weak to Very strong.
Can I generate several passwords at once?
Yes. Set the quantity to generate up to ten passwords in one go, each with its own copy button, and use Copy All to grab the whole list. Every password uses the same secure random source, so you can pick whichever you like or keep several for different accounts.
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