Diceware passphrase generator
Roll, read the code, find the word. Do it with secure virtual dice here, or roll real dice and use this page as your wordlist lookup.
How diceware works
The method is simple enough to do at a kitchen table. Five dice give a number from 11111 to 66666, and there are exactly 7,776 such numbers. The wordlist has one word per number. Because a fair die can't favour any face, every word is equally likely, and the passphrase's strength follows directly: words × log2(7,776).
Rolling well
- Roll all five dice at once, then read them in a fixed order (left to right). Don't re-roll a word because you don't like it: rejecting words shrinks the list and the entropy.
- Casino dice are the most precise, but any ordinary dice are fine for this purpose.
- Keep the paper away from cameras and bin it (shredded) once you've memorised the phrase.
The EFF's 2016 article introducing these lists, by Joseph Bonneau, explains why they replaced the original diceware words with ones that are easier to spell and remember. Want the words picked instantly instead? Use the one-click passphrase generator. It does the same maths with the same list.
Questions
What is diceware?
Diceware is a method for making passphrases with ordinary six-sided dice, published by Arnold Reinhold in 1995. You roll five dice, read the numbers as a code such as 43152, and look up the word on that row of a 7,776-word list. Repeat for each word.
Why 7,776 words?
Five dice have 6 × 6 × 6 × 6 × 6 = 7,776 possible outcomes, so each outcome maps to exactly one word. That is log2(7,776) ≈ 12.92 bits per word.
Are virtual dice as good as real ones?
These virtual dice use crypto.getRandomValues with rejection sampling, which gives each face exactly a one-in-six chance. Physical dice are the choice if you don't want to trust any computer; roll them and type the codes into the lookup box.
What is the difference between the original diceware list and the EFF list?
Reinhold's original list includes short fragments, numbers and obscure words. The EFF long list (2016) replaced them with longer, familiar, concrete words that are easier to remember and type. Both have 7,776 entries, so the strength per word is identical.
Can I print the list?
Yes. The EFF publishes the lists as plain text at eff.org/dice under a CC BY 3.0 US licence. Print one, roll real dice, and your passphrase never touches a computer until you first type it.