Diceware Passphrase Generator
A diceware passphrase generator creates passphrases using randomly selected words from the EFF (Electronic Frontier Foundation) wordlist — the gold standard for passphrase generation. Each word adds ~11 bits of entropy, making a 5-word diceware passphrase highly secure and genuinely memorable.
What is the diceware method?
Diceware was invented by Arnold Reinhold in 1995. The original method uses physical dice — roll five dice, look up the resulting number in a wordlist, and repeat for each word. The digital equivalent uses a cryptographically secure random number generator to select words with equivalent randomness. Each word selection from a 2,000-word list provides ~11 bits of entropy. A 5-word passphrase achieves ~55 bits.
Why diceware passphrases are secure
Security comes from the size of the word selection space. With 2,000 words and 5 selections, there are 2000^5 = 3.2 × 10^16 possible passphrases. An attacker performing a dictionary attack on passphrases (rather than individual passwords) would need to test all these combinations. At 100 billion guesses per second, exhausting the space would take years.
Frequently Asked Questions
Diceware uses physical dice or a CSPRNG to randomly select words from a wordlist. Each word is chosen independently with uniform probability. The method was invented by Arnold Reinhold in 1995 and is endorsed by security experts including Bruce Schneier.
A 4-word diceware passphrase (~44 bits) suits most everyday accounts. Use 5 words (~55 bits) for important accounts, and 6+ words (~66+ bits) for your password manager master password or any credentials protecting multiple other accounts.
For passwords you must memorize, diceware is superior — comparable entropy with much better memorability. For machine-stored passwords (in a password manager), a random 16+ character password is equally secure and slightly more compact.
Yes — a 6-7 word diceware passphrase is the ideal master password for a password manager. It's strong enough for the task and memorable enough that you can type it reliably. Practice typing it a few times when you first set it.