Passphrase Generator
Free Diceware passphrase generator — memorable multi-word passphrases from the EFF wordlists, with entropy shown per phrase. Six words is about 77 bits. Generated locally in WebAssembly; nothing is uploaded.
Runs entirely in your browser — nothing you enter is uploaded or stored.
Diceware, without the dice
A passphrase is generated by choosing whole words at random from a published list. The original method used five dice rolls to index a 7,776-word list — hence Diceware — and the arithmetic is the point: each word contributes log₂(7776) ≈ 12.9 bits, so six words give about 77 bits regardless of how ordinary the words look.
Why the list being public does not matter
This is the part that trips people up. Knowing the wordlist does not help an attacker, because they already have to try every combination — and there are 7,776⁶ of them. What doeshelp an attacker is a human choosing the words, because humans pick memorable phrases and grammatical sequences from a far smaller effective set. The security is in the rolling, not the list.
Correct horse battery staple
The xkcd comic that popularised this is right about the mechanism and optimistic about the numbers: four common words is around 44 bits, which is fine for a low-value account and not enough for a password manager's master key. Six words is the usual modern recommendation, seven or eight if it is protecting everything else you own.
Frequently asked questions
Is a passphrase really as strong as a password?
Stronger, for the same amount of human effort. Six words from the EFF long list is about 77 bits — comparable to a 13-character random password, and far easier to remember and to type on a phone. Strength comes from the number of words, not from their length or from adding punctuation.
Does it matter that the wordlist is public?
No, and assuming otherwise is a common mistake. Security here comes from the number of possible combinations, not from secrecy of the list. Six words drawn from 7,776 gives 7776^6 possibilities — about 2.2×10^23 — and an attacker knowing the list does not reduce that. What would reduce it is picking the words yourself instead of rolling for them.
Which wordlist should I choose?
EFF long by default: 7,776 words at 12.9 bits each. The short lists trade bits per word for shorter, more typeable words — useful when entering the passphrase on a TV remote or a games console. Short list #2 has unique three-letter prefixes, so autocomplete can finish each word.
Should I add a number and a symbol?
Only if a password policy forces you to. They add a couple of bits and cost a lot of memorability. Adding one more word adds thirteen bits. If you have the choice, choose the word.