Dev & Data
Password & passphrase generator
Choose a length and the characters to include, or switch to a passphrase of random words. Five fresh options are made each time. Nothing leaves your device.
- Free, no sign-up
- Runs in your browser
- Nothing uploaded
Settings
Type
Result
Table
How it works
Strength comes from unpredictability. The generator uses your browser's cryptographic random number source, with rejection sampling so every character or word is equally likely. A password that includes at least one character of each ticked kind is shuffled so those characters do not sit in a fixed place.
The entropy figure is length times the logarithm of the pool size, in bits. The crack time assumes an attacker who has stolen a database and can try 10 billion guesses a second, which is a pessimistic case for a fast hash. Websites that limit login attempts are far harder to attack.
Passphrases use the EFF Short Wordlist (1,296 words, about 10.3 bits a word). Five words is about 51 bits, and six or more is better for something you protect heavily. Word list by the Electronic Frontier Foundation, licensed CC BY 3.0 US.
Frequently asked questions
Is this safe to use?
The password is generated on your device and never sent anywhere or stored. As always, save it in a password manager rather than a note.
Passphrase or password?
Use a passphrase for something you must type or remember, such as a manager master password. Use a long random password for everything else.
How long should it be?
At least 14 characters for a random password, and 5 or more words for a passphrase.