Password Generator
Generate strong, random passwords with custom length and character options using this free password generator that runs in your browser.
Generated with your browser's secure random generator. Nothing is sent or stored — refresh and it's gone.
How to use this calculator
- Set the length and tick the character types you want.
- Press the refresh button for a new password, then Copy. Optionally exclude look-alike characters.
How it works
Each character is drawn from your chosen set using the browser's cryptographically-secure random generator (with bias-free sampling).
The strength estimate is the Shannon entropy: log₂(character-set size) × length, in bits — more length and more character types mean a stronger password.
Worked example
16 chars, all types. ≈ 105 bits of entropy — very strong.
Common mistakes
- Going too short — under about 12 characters is easy to brute-force; longer is the single biggest win.
- Reusing one password everywhere — generate a unique one per site and store them in a password manager.
Frequently asked questions
Is this safe — are passwords sent anywhere?
No. Generation happens entirely in your browser using crypto.getRandomValues; nothing is transmitted or stored. Refresh the page and it's gone.
How long should my password be?
Aim for at least 12–16 characters with a mix of types. Longer is stronger; a passphrase of several random words is a good alternative.
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Cite this tool
Zerdly. (2026). Password Generator. Retrieved from https://www.zerdly.com/tools/password-generator/
Tip: Enter any known values to calculate the remaining results.
Designed to run locally in your browser. Tool inputs are not intentionally stored by Zerdly unless stated otherwise.