Password Generator
Generate strong random passwords or word passphrases with a cryptographic RNG. Runs entirely in your browser — nothing leaves your device.
Generate a strong password in your browser
Create a random password or word passphrase with a cryptographic RNG. Everything runs locally in your browser — the generated secret never leaves your device or touches a server.
Modes
- password — a random string of length characters. Lowercase is always included; toggle uppercase, digits, and symbols to widen the alphabet (and the entropy).
- passphrase — words random words joined by your separator (e.g.
able-fire-coat-desk). Easier to type and remember than a symbol soup.
The output shows the result plus its estimated entropy in bits (higher is stronger). Re-run for a fresh value.
Tips
- Aim for 16+ characters (passwords) or 4+ words (passphrases).
- Use a unique password per site and store them in a password manager.
FAQ
Is the randomness actually cryptographically secure?
Yes — characters and words are drawn from the platform's CSPRNG (the browser's
crypto.getRandomValues when running as WebAssembly on this page), and indices
are sampled uniformly, so there's no modulo bias skewing some characters to
appear more often. This is the same class of RNG password managers use.
How is the entropy-in-bits number calculated?
It's length × log2(alphabet size). With all classes on, the alphabet is 85
characters (26 lower + 26 upper + 10 digits + 23 symbols) ≈ 6.4 bits per
character, so a 16-character password scores ≈ 102 bits. Turning off classes
shrinks the alphabet and the score. For passphrases it's
words × log2(120) ≈ 6.9 bits per word.
Why does a 4-word passphrase show far less entropy than a 16-character password?
Because the built-in word list has 120 words, each word contributes only ~6.9 bits — 4 words ≈ 28 bits, versus ~102 bits for a full-alphabet 16-character password. Passphrases trade raw entropy for memorability; add more words (the tool allows up to 20) to close the gap.
What limits and character sets does the generator use?
Password length can be 1–512 characters (default 16); passphrases take 1–20
words (default 4) joined by a separator you choose (default -). Lowercase
letters are always included; uppercase, digits, and the symbol set
!@#$%^&*()-_=+[]{};:,.? are individually toggleable and all on by default.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool password-generator 'mode=password'New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/password-generator/?mode=password&length=16&words=4&uppercase=true&digits=true&symbols=true&separator=-Machine-readable descriptor: tool.json — title + parameters JSON Schema for agents.