Passphrase generator
Random multi-word passphrases from the EFF diceware list: strong enough for a password manager’s master password, easy enough to type on a phone.
Offline brute force at 100 billion guesses a second: 35 thousand years.
Press generate to fill this table.
How diceware works
Diceware was devised by Arnold Reinhold in 1995. You roll five physical dice, read the result as a five-digit number such as 4-3-6-1-2, and look it up in a list of 6⁵ = 7,776 words. Repeat for each word. RandomKit does the same with your browser’s cryptographic random generator instead of dice. If you’d rather use real dice, the EFF publishes the numbered list, and our dice roller handles 5d6.
The word list is the EFF long list (CC BY 3.0 US), bundled with the page, so no request is made when you generate.
Questions people ask
How secure is a diceware passphrase?
Each word from the 7,776-word EFF list adds log₂(7776) ≈ 12.9 bits of entropy. Five words give about 64.6 bits, six about 77.5 and seven about 90.5. The EFF recommends at least six words for important accounts.
Is it safe that the word list is public?
Yes. The security comes from choosing words at random, not from hiding the list. An attacker who knows the exact list still has to try 7,776⁶ (about 2.2 × 10²³) combinations for a six-word phrase.
What is the EFF word list?
The Electronic Frontier Foundation published its long word list in 2016 as an improvement on Arnold Reinhold’s original Diceware list. It avoids profanity, hard-to-spell and easily confused words, and every word is 3 to 9 letters long.
Do capitals, numbers and separators help?
A little. Adding a random digit adds about 3.3 bits, and a random symbol separator a few more. Adding one more word adds 12.9 bits, so length is still the better lever. Use the extras when a site insists on them.