Passphrase generator
Random words from the EFF Diceware list, chosen by your browser’s cryptographic random number generator. Strong enough for a master password, easy enough to remember.
How Diceware turns dice into words
Roll five six-sided dice. Read them left to right as a five-digit number. Each number from 11111 to 66666 points to exactly one of the 65 = 7,776 words on the EFF list. Tap a die to change it, or roll all five.
Every word is equally likely, so each one adds log2(7,776) ≈ 12.9 bits. Six words: 77.5 bits, or about 2 × 1023 possible passphrases. The attacker can know you used this list and this method; the randomness is what they can’t guess.
Why passphrases work
People are bad at remembering random characters and good at remembering odd little scenes. A passphrase trades a longer password for one you can picture: “plaza”, “jelly”, “refinish”. The strength doesn’t come from the words being obscure. It comes from them being picked at random from a large, public list.
How many words for what
| Words | Entropy | Good for |
|---|---|---|
| 4 | 51.7 bits | Low-value accounts behind rate-limited logins |
| 5 | 64.6 bits | Everyday accounts |
| 6 | 77.5 bits | Email, banking, password manager master password (EFF’s recommendation) |
| 7+ | 90.5+ bits | Disk encryption, crypto wallets, anything attacked offline |
About the word list
We use the EFF large wordlist published by the Electronic Frontier Foundation in 2016. Its words are common, easy to spell, 3 to 9 letters long, and avoid offensive or easily confused words. It replaced Reinhold’s original 1995 list, which included odd fragments like “aaa” and “zz”.
Need a password in characters instead? Use the password generator. Want to check a passphrase you already use? Try the password strength checker.
Questions people ask
What is a passphrase?
A passphrase is a password made of several randomly chosen words, such as “stadium-uncover-plaza-refinish-jelly-frosted”. Because each word is picked at random from a list of 7,776, six words give about 77.5 bits of entropy while staying far easier to remember and type than a random character string.
How many words should my passphrase have?
The EFF recommends at least six words from its large list for anything important. Five words (about 64.6 bits) is fine for everyday accounts behind rate-limited logins. For a password manager master password or disk encryption, six or seven words.
What is Diceware?
Diceware is a method, created by Arnold Reinhold in 1995, for picking passphrase words with ordinary dice: roll five dice, read the digits as a number such as 43516, and look it up in a list of 7,776 words. This generator uses the EFF’s 2016 improved list and replaces the dice with your browser’s cryptographic random number generator.
Is “correct horse battery staple” still a good password?
The method from that xkcd comic is sound: four random common words beat a short complex password. That exact phrase is now famous and sits in every cracking dictionary. Generate your own, and use five or six words rather than four.
Do separators, capitals or an added number make it stronger?
Slightly. A random separator or a random digit adds a few bits, and they help when a site demands mixed character types. The real strength comes from the number of randomly chosen words. The strength readout on this page counts only what is actually random.
Can I pick my own words instead?
Words you choose yourself are far more predictable than random ones, because people favour meaningful, related words. The entropy numbers here only hold for words picked at random.