Passphrase Generator
Create a random passphrase of real words that is easy to remember and type but very hard to guess. Pick the number of words and the style, and see exactly how many bits of entropy it has. Everything is generated on your device.
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Your passphrases
Words and their dice numbers
Use real dice instead (diceware)
Roll five six-sided dice for each word and type the five numbers (for example 35214). Separate words with spaces or new lines. Nothing leaves your device either way.
Strength by number of words
Average time to guess = half of all combinations ÷ guesses per second. "Online" assumes 1,000 guesses/s against a website with rate limits; "offline" assumes 100 billion guesses/s against a leaked fast hash. Words only, separators and extras not counted.
How to use the Passphrase Generator
- Choose the number of words: 6 words gives about 77 bits, enough for most uses; use 7 or more for a password-manager master password.
- Pick a separator and capitalization that the site you are using accepts.
- Add digits or a symbol only if a site's password rules demand them; the words already provide the strength.
- Click Generate passphrase until you get one you like, then click Copy.
- Store it safely: memorize it or save it in a password manager, and never reuse it on another site.
How passphrase entropy is calculated
Entropy measures how many guesses an attacker needs. When every word is picked uniformly at random from a list of L words, a passphrase of n words has H = n × log2(L) bits of entropy. With L = 7,776, each word adds 12.925 bits, so 6 words = 77.5 bits, or 7,7766 ≈ 2.2 × 1023 possible passphrases. An attacker must try half of them on average.
Extras add less than you might expect: random capitalization of each word adds 1 bit per word, a random digit added to a random word adds log2(10) + log2(n) bits, and a random symbol from 12 adds log2(12) + log2(n) bits. Fixed choices, such as always capitalizing the first letter or always using a hyphen, add nothing because the attacker can assume them.
| Use | Suggested length | Entropy |
|---|---|---|
| Low-value website login (with rate limiting and 2FA) | 4–5 words | 52–65 bits |
| Email, banking, Wi-Fi (WPA2/WPA3) key | 6 words | about 77 bits |
| Password-manager master password | 7 words | about 90 bits |
| Disk encryption, PGP or SSH key passphrase, crypto wallet | 8 words or more | 103+ bits |
Rolling a passphrase with real dice
If you prefer not to trust any computer, use five ordinary six-sided dice. Roll all five, read them left to right (for example 3-5-2-1-4 gives 35214), and type the number into the real-dice box to see the word. Repeat once per word. The dice number shown under every generated word is simply the word's position in the sorted list written in base 6, so the two methods use exactly the same list.
- Do not reroll because you dislike a word, and do not rearrange words into a sentence: both reduce the randomness.
- Write it down safely until it is memorized, then destroy the note or keep it somewhere locked.
- One passphrase per account. Use a password manager for everything else, protected by one strong passphrase, and turn on two-factor authentication.
- Check an existing password with the Password Strength Checker, or create random character passwords with the Password Generator.
Frequently asked questions
What is a diceware passphrase?
Diceware is a method, published by Arnold Reinhold in 1995, for choosing passphrases with true randomness. You roll five dice to get a number from 11111 to 66666, look the number up in a list of 7,776 words (6^5), and repeat for each word. Because each word is chosen uniformly at random, the strength can be calculated exactly. This tool does the same with your browser's cryptographic random number generator, and also lets you look up words from physical dice rolls.
How many words should my passphrase have?
Each word from a 7,776-word list adds log2(7776) ≈ 12.9 bits of entropy. Five words give about 64.6 bits, six words about 77.5 bits and seven words about 90.5 bits. Six words is a good default for important accounts; use seven or more for a password manager's master password or disk encryption, where an attacker could try guesses offline.
Is a passphrase stronger than a random password?
Per character, a random password is denser, but strength depends on entropy, not on how complex it looks. A six-word passphrase (about 77 bits) is as strong as a random 12-character password using upper, lower case letters and digits (about 71 bits) or stronger, and it is much easier to remember and type. NIST SP 800-63B recommends allowing long passphrases for this reason.
Do capital letters, digits and symbols make it much stronger?
Only a little. Capitalizing each word adds nothing an attacker would not try. Random capitals add 1 bit per word, and one random digit after a random word adds about 3.3 bits plus the position. Adding one more word adds 12.9 bits, so a longer passphrase is the better way to gain strength. Use digits and symbols mainly to satisfy site rules.
Is the entropy still valid if an attacker knows the word list?
Yes. The entropy figure already assumes the attacker knows the exact list, the number of words and your settings. The security comes only from the random choices, which is why the words must be picked by the generator or real dice, not by you. Human-chosen phrases such as song lyrics are far weaker.
Is it safe to generate a passphrase on a website?
This page creates passphrases entirely in your browser with crypto.getRandomValues. Nothing is sent to a server, logged or stored; only your option choices are remembered in your browser. For maximum assurance you can disconnect from the internet after the page loads, or use the real-dice mode.
Which word list does this tool use?
A list of 7,776 common, easy-to-type English words of 4 to 8 letters, filtered to remove offensive words, abbreviations and names. It has the same size as the standard diceware and EFF large wordlists, so every word adds the same 12.9 bits. Dice numbers shown under each word match this list, not other published lists.
Are all the tools on FreeToolCabin tested for quality and accuracy?
Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.