Password Generator
Generate cryptographically secure, customizable random passwords in your browser.
Click Generate to create passwords.
About the Password Generator
This generator builds passwords entirely in your browser using window.crypto.getRandomValues, the same cryptographically secure random number source browser-based cryptography relies on — never the predictable Math.random. No password ever leaves your device or touches a server; you can confirm this yourself in your browser's network tab. Entropy, shown in bits, is length × log₂(charset size) — for example, a 16-character password using all four classes (26 + 26 + 10 + roughly 32 symbols ≈ 94 characters) has about 16 × log₂(94) ≈ 105 bits of entropy, meaning an attacker would need on the order of 2¹⁰⁵ guesses to exhaust the possibilities by brute force — far beyond what's practical with any current computing power.
To use it: drag the length slider, toggle which character classes to include (uppercase, lowercase, numbers, symbols), optionally exclude visually similar characters like I, l, 1, O, and 0, then click Generate for a fresh batch of five candidates with a copy button on each. Dropping a character class shrinks the charset and lowers entropy at the same length — for instance, removing symbols and numbers from a 16-character password (down to a 52-character alphabet) drops entropy from ~105 bits to about 16 × log₂(52) ≈ 91 bits, still strong but a meaningfully smaller search space for an attacker.
How is randomness generated?+−
Every character is chosen using window.crypto.getRandomValues, the browser's cryptographically secure random number source — never Math.random.
What does entropy mean here?+−
Entropy in bits measures how many guesses a brute-force attacker would need: length × log2(charset size). Higher is harder to crack.
What password length should I use?+−
Most current guidance recommends at least 12-16 characters for everyday accounts, and longer for anything sensitive. This tool supports up to 128 characters — length matters more for security than character variety once you're above a reasonable minimum.
Why exclude similar-looking characters like I, l, 1, O, and 0?+−
Enable this if you'll be typing the password by hand or reading it off a screen or printout — it trades a small amount of entropy for fewer transcription mistakes, which matters less if you're copying the password directly into a password manager.
Are the five generated passwords related to each other?+−
No — each one is generated independently from a fresh batch of cryptographically random values. Seeing multiple options at once just saves you from clicking Generate five times.
Is it safe to generate a password for a real account in a browser tool?+−
Yes for this generator specifically — it never sends any data over the network (check your browser's network tab to confirm) and uses the same crypto API real password managers use. As general practice, avoid password generators that don't disclose how randomness is sourced.
Should I reuse a strong generated password across multiple sites?+−
No — even a high-entropy password should be unique per account, since reuse means one breached site compromises every other account using that password. Use this generator alongside a password manager to keep track of unique passwords per site.