The Diceware method is a technique for generating strong and secure passwords or passphrases. Developed by Arnold G. Reinhold, it relies on the use of dice to select random words from a predefined list. The strength of Diceware lies in the randomness introduced by the dice rolls and the use of a large word list. This randomness enhances the security of the generated passphrase, making it resistant to common password attacks. In this guide, we'll walk you through the process of creating Diceware passwords in Microsoft Excel.
Warning
Note that it is recommended that no Diceware password should be generated using a software. Using an actual dice instead of a random number generator and using pen and paper to write them down will give results with no bias from a software algorithm.
You can access detailed information about this method on The Diceware Passphrase Home Page.
We recommend using this Excel method for educational purposes only.
Diceware
Diceware is a password (or passphrase) generation method using ordinary dice for generating random numbers. Five rolls of a six-sided dice create a five-digit number which corresponds to word in a prepared word list. Concatenating multiple words this way, you can create a strong password.
For example, the following table illustrates 3 words generated from 15 rolls.
| Roll 1 | Roll 2 | Roll 3 | Roll 4 | Roll 5 | Word | |
| Set 1 | 2 | 3 | 3 | 3 | 5 | double |
| Set 2 | 6 | 2 | 1 | 5 | 3 | tune |
| Set 3 | 5 | 3 | 1 | 2 | 2 | saxon |
These words generate the following password phrase: “doubletunesaxon”.
Although this password might seem weak, it has more password entropy than a password like “P@ssW0rd” which includes upper case letters, a number and a non-alphanumeric character.
Password Strength Test: http://rumkin.com/tools/password/passchk.php[/box]
Generate Diceware passwords in Excel
First of all, you need a word list which includes 6<sup>5</sup> = 7776 words with corresponding five-digit numbers. In our example, we are using the original list from https://theworld.com/~reinhold/diceware.wordlist.asc. Alternatively, you can create your own list or choose from other options provided below:
Copy the word list you prefer into Excel. We have converted the list into an Excel Table to make using formulas easier.
To mimic the dice, you need a random number generator which can return an integer between one and six. Either the RANDARRAY or RANDBETWEEN function can be used to generate these numbers. Remember that you need to be a Microsoft 365 subscriber to use the RANDARRAY function.
In this example, we used the RANDARRAY function which can populate the random numbers with a single formula.
The StringCount is the name of the cell G3 which determines the number of words to be generated. In general, five (5) or six (6) words are stronger than most of the passwords. You can use seven (7) or eight (8) words for critical accounts like a crypto wallet. Nine (9) is usually an overkill.
The next step is to find the words corresponding to the generated numbers. A lookup function like the brand new XLOOKUP or traditional VLOOKUP and INDEX functions will work here.
The final step is to merge the words. Remember that the password will update with each calculation! For this, copy the results when you are satisfied with the generated password.
Using Diceware method through Excel provides a great way of generating strong and memorable passwords. By blending a diverse word list with randomization, users can enhance the security of their online accounts effectively.
