Approx bits (403-word list)
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Diceware Passphrase Generator
Diceware Passphrase Generator is a diceware worksheet. Default 6 words, new each run.
Page updated 2026-09-14.
Calculator
Calculated Results
Honest bits, not classic Diceware's bits
A passphrase is only as strong as the math says it is. This page draws words uniformly at random from its own 403-word list using a cryptographically secure random source, and reports bit strength for that exact list, not for the larger 7,776-word list classic Diceware uses.
Default: 6 words from a 403-word list. Bits = 6 x log2(403) = about 51.9 bits. Add a word or two if you want to approach classic Diceware's per-word strength with a shorter word list.
Related tools
For a character-based (not word-based) password, see the Password Generator. For a quick strength estimate of a length-and-alphabet password, see the Password Strength Entropy Calculator.
Frequently Asked Questions (FAQ)
How is the passphrase generated?
Each word is picked independently and uniformly at random from a 403-word list using crypto.getRandomValues (not Math.random), the same cryptographically secure source used by the site's other random-generator tools.
How is the bit strength calculated?
Bits = word count x log2(word list size). With a 403-word list, that is about 8.65 bits per word, so a 6-word phrase is about 51.9 bits. Classic Diceware uses a 7,776-word list (5 dice rolls per word) for about 12.9 bits per word -- this page's shorter list is weaker per word, and the bit count now reflects that honestly.
Is this as strong as classic Diceware?
No, not per word. Classic Diceware's 7,776-word list gives about 12.9 bits per word; this page's 403-word list gives about 8.65 bits per word. Use one or two extra words here to reach a comparable total, or use a full 7,776-word Diceware list offline for the standard.
Does this send my passphrase to a server?
No. Generation runs entirely in this browser using the Web Crypto API. Nothing is transmitted or logged.
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