Passphrase generator
Easy to remember. Impossible to guess.

Random words like Maple-Orbit7-Kettle-Dune are easier to type than t#9Lq!vZ, and far harder to crack once there are enough of them. Every word is drawn by the Web Crypto API from a list of 1,829 common English words.

Very strong

Calculating…

Time to crack your new passphrase

Measuring…

Worst case: an offline attack on a fast hash by a GPU cluster testing one trillion guesses per second.

You are here
  1. 1 second
  2. 1 hour
  3. 1 year
  4. A lifetime
  5. The pyramids
  6. Since the dinosaurs
  7. Age of the universe

The numbers

How strong is a passphrase?

Each random word adds 10.8 bits of entropy. Here is what that means against the worst case: a GPU cluster making a trillion guesses per second against a fast hash.

LengthEntropyGPU cluster needsWith a numberGPU cluster needs
4 words43 bits6 seconds52 bits37 minutes
5 words54 bits3 hours63 bits2 months
6 words65 bits7 months74 bits356 years
7 words76 bits1.1 thousand years85 bits759 thousand years
8 words87 bits2 million years96 bits1.6 billion years
9 words98 bits3.6 billion years107 bits3.3 trillion years

Most real sites store passwords with slow hashes such as bcrypt or Argon2, which slow attackers down by a factor of millions. These figures are the floor, not the typical case.

Why it works

Random words beat clever sentences.

The machine must choose

People pick predictable phrases: song lyrics, quotes, sports teams. Cracking tools ship with all of them. A passphrase is only strong when every word is picked at random from a large list, which is exactly what this generator does.

Length does the heavy lifting

Six random words from our list give about 10.8 × 6 bits of entropy. Add a seventh word and an attacker's work grows by a factor of 1,829. No symbol substitution comes close to that.

Made for passwords you type

Use passphrases where a password manager cannot fill in for you: the manager's master password, your computer login, a Wi-Fi key you read out to guests, or a disk encryption password.

Where random characters win

Some sites cap passwords at 16 or 20 characters. There, a random password packs more strength per character. For everything stored in a manager, random characters are perfect.

Questions

Passphrase FAQ

What is a passphrase?

A passphrase is a password made of several words, like Maple-Orbit7-Kettle-Dune. When the words are picked at random, it is as strong as a long random password but much easier to type and remember.

How many words should my passphrase have?

Use at least 6 random words for important accounts, and 7 or more for a password manager master password or a disk encryption key. Each extra word multiplies the number of guesses an attacker needs by about 1,829.

Is 'correct horse battery staple' still a good passphrase?

Not anymore. It became famous, so it is in every cracking dictionary. The idea behind it is still right: the words must be chosen at random by a machine, not by a person, and never copied from an example.

Should I add numbers or symbols to a passphrase?

It helps a little, and some sites require it. The generator can add a random number at a random position. Adding more words gives you far more strength than swapping letters for symbols.

Is this the Diceware method?

It follows the same principle as Diceware: each word is selected uniformly at random from a fixed list. Instead of dice, it uses your browser's cryptographic random number generator, with unbiased sampling.

Are my passphrases sent or saved anywhere?

No. The word list is downloaded once with the page, and every passphrase is assembled locally in your browser. Nothing is sent, stored or logged, and the tool works offline.