Diceware passphrase generator

Diceware turns dice rolls into words: five six-sided dice give 6⁵ = 7,776 possible results, and each result points to one word in the EFF Large Wordlist. One word is worth about 12.9 bits, so six words, or 30 rolls, give about 77.5 bits. Because the dice are the only source of chance, you can make a strong passphrase without trusting any computer.

What Diceware is

Diceware is a method from the mid-1990s for making passphrases with ordinary dice and a printed list. Its appeal is that the randomness is something you can see. Nobody has to trust that a program, a phone or a website picked fairly; you watched the dice land.

This page uses the EFF Large Wordlist, which the Electronic Frontier Foundation published in 2016 as an easier-to-use alternative to the original Diceware list, with its rare words and odd strings. It has exactly 7,776 entries, each between 3 and 9 characters, chosen to be familiar, easy to spell and free of the most offensive terms. Next to every generated word the tool shows its dice code, so the on-screen result can be checked against EFF's list, and so you can see exactly how the method works before you try it by hand.

What the five digits mean

Each word in the list carries a five-digit code made only of the digits 1 to 6, one digit per die. The codes run in order like an odometer that counts to six instead of nine:

Five dice with six faces each can land in 6 × 6 × 6 × 6 × 6 = 7,776 ordered ways, one for every word. Order matters: 13132 and 31312 are different codes and different words, which is why you read the dice in a fixed order rather than sorting them.

Roll your own passphrase with real dice

1. Get five six-sided dice, or one die you will roll five times, and either a copy of the EFF Large Wordlist or this page's lookup box.
2. Roll all five dice at once and read them in a fixed order, for example left to right, writing the five digits down.
3. Find that five-digit code in the list, or type it into the lookup box, and write down the word that matches.
4. Repeat until you have six words, which takes 30 rolls in total.
5. Keep the words in the order you rolled them and store the passphrase somewhere safe, then destroy any scrap paper you used.

If you use one die, roll it five times per word and write each result in sequence. If your dice are different colors, a rule such as "red first, then blue" works just as well as left to right. EFF's own instructions say to roll all five at once and note the faces before looking at the list.

Or let the page roll

Press Generate and the browser picks the words for you, showing the dice code beside each one. The word count defaults to six and goes from 3 to 12, and the words are separated by spaces unless you pick another separator. There is no option to add a digit here; if a site insists on one, the passphrase generator, which uses the same list, can add it.

If you rolled real dice, use the lookup instead: type the five digits of a roll and the page shows the matching word, so you do not need a printed list at all.

A worked example from one press of the button: 13132 bacon, 31163 flatware, 21655 custard, 44562 police, 45462 promotion, 36261 liver. Look up any of those codes in the EFF file and you will find the same words. (Never use a passphrase that has been printed on a web page, including this one.)

Why a public list is still safe

The list is published on purpose. Its security does not come from secrecy; it comes from counting. With six words there are 7,776⁶, or about 2.2 × 10²³, equally likely passphrases. Someone who has the list, knows you used six words and has a fast computer still has to search that space, and on average they need half of it.

As a sense of scale: suppose an attacker can test ten billion candidates per second, the speed of one top gaming GPU on an unsalted SHA-256 hash. Working through half of the six-word space would take about 350,000 years. At a trillion guesses per second it would take about 3,500 years. Slow password hashes and login limits stretch those figures much further.

Getting the dice part right

• Do not reroll words you dislike. Rejecting words, even occasionally, shrinks the set of possible results and skews it toward words people prefer. If a word is unusable, start the whole passphrase again.
• Do not rearrange the words. Choosing an order that "sounds better" leaks a little of the randomness into your preferences.
• Use reasonable dice. Any normal die is far better than a person picking words. Precision dice are the most even, but the slight unevenness of an ordinary die matters much less than human choice would.
• Roll somewhere private. A camera or a curious housemate sees the same numbers you do.
• Write clearly. A misread 6 for a 5 gives you a different, equally strong word, but you need to know which one you chose.

When to use dice, and when to use the button

Dice are for people who want the passphrase to come from something outside any device: for a password manager's master password, a disk-encryption key, or a recovery phrase kept in a safe. The button is for everyday use. Both draw from the same 7,776 words with the same odds per word, so the strength figures are identical.

What the page keeps

Nothing. Words are drawn in your browser from a list bundled with the page. There is no upload, no history, and no copy saved anywhere. Rolls you type into the lookup are matched against that same local copy of the list, so they never leave the device either. If you roll physical dice and use a printed list, the page is not involved at all.

How the electronic rolls work

Each word is one random draw of a list position using crypto.getRandomValues; draws that would favor some positions are rejected and repeated, leaving all 7,776 equally likely. The five-digit code shown beside a word is the one printed next to it in the EFF file, which is simply its position counted in base six with the digits 1 to 6 instead of 0 to 5. The list is the EFF Large Wordlist, reproduced unchanged under its Creative Commons Attribution license and credited on the licenses page. You can read about checking for network traffic in the methodology.

FAQ

Do I need five dice?

No. One die rolled five times gives exactly the same result, as long as you write the rolls down in the order they happened.

What if a die lands tilted against something?

Roll it again. Only a cleanly landed face counts; rerolling an unreadable die does not bias the outcome.

Can I use the dice codes with EFF's printed list?

Yes. The codes on this page match the EFF Large Wordlist file exactly, so you can generate here and check on paper, or roll at home and type each code into the lookup to confirm the word.

How many words should I roll?

Six for most uses, which is also EFF's recommendation. Seven or eight for anything an attacker could test offline, such as an encrypted drive or a password manager vault.

Does this tool support the EFF short lists?

No. The short lists use four dice and 1,296 words, so each word is worth less (about 10.3 bits). This page uses only the large list and five dice.

Is Diceware the same as a passphrase generator?

The output is the same kind of thing. Diceware is the name of the dice method; a passphrase generator does the rolling for you. This page shows the dice codes so you can do either.

Sources

• EFF Dice-Generated Passphrases
• EFF wordlists announcement (2016)
• EFF Large Wordlist file

Checked 2026-10-11.

Last updated: 2026-10-17