Effect of Compromised Dice on Dice Generated Passphrases

The 2016 fundraiser for the Electronic Frontier Foundation provided 6-sided dice to their donors. These dice are supposed to be used to generate diceware passphrases.

Their fundraising campaign was so popular that they didn't have enough dice to give to all of their donors. This made me wonder... if someone was able to convince the factory that makes the EFF dice to make them weighted, how much would this help.

To get examples of passphrases generated in your browser, head to our Passphrase Generator

The page below computes the probabilities for each of the words from the new EFF long wordlist given dice that have the probabilities from the inputs below. At the bottom of the page it lists the most probable words given the weighting that you choose.

The expected number of guesses for a single word that is reported is the number of guesses that would have to be made, if the attacker was going down the list from most-probable to least-probable, before they had a greater than 50% chance of having guessed it already.

Probabilites of Sides

The expected number of guesses for a single word:

Probability of Passwords

List of most probable words in descending order