About the Passphrase
This diceware generator builds passphrases by picking whole words at random from a curated 195-word list, using the same crypto.getRandomValues source as a proper random password generator rather than Math.random. You choose how many words to string together, from 2 to 12, the separator between them, and whether to capitalize each word or append a random two-digit number.
Diceware is the classic technique for building passphrases whose strength is easy to reason about. Because each word is drawn independently from a fixed list, entropy grows by a fixed amount per extra word: roughly 7.6 bits per word with this tool's 195-word list, plus close to 6.6 bits if you append a number. A live estimate in bits, with a plain-language strength label, updates as you change the settings.
Passphrases exist because dense random-character passwords are strong but hard to remember and slow to type on a phone keyboard or in front of someone. A sequence of ordinary words strung together with a separator is much easier to recall and retype correctly, at the cost of needing more words to reach the same entropy as a shorter random password.
Use it for secrets you have to type from memory: a master password for a password manager, a disk-encryption passphrase, an SSH key passphrase, or a shared Wi-Fi password you need to read out loud to guests. For anything you will only ever copy and paste and never memorize, the plain password generator packs more entropy per character.
Word selection happens entirely in your browser. Nothing is sent to a server, so the resulting passphrase never leaves your device before you copy it.
How to use it
- Set the number of words with the slider, from 2 up to 12 (default 5).
- Pick a separator: hyphen, dot, space or underscore.
- Toggle capitalize to uppercase the first letter of every word.
- Toggle add number to append a random two-digit number after the last word.
- Read the live entropy estimate in bits and its strength label.
- Click regenerate for a fresh passphrase with the same settings.
- Click copy to place it on your clipboard.
Examples
- 4 words, hyphens, no number: Cedar-Amber-Quill-Otter, about 30 bits, labeled weak, fine only for a low-value throwaway login.
- 6 words, capitalized, spaces, with a number: Ocean Ember Quartz Bison Ivory Panda 47, about 52 bits, labeled ok.
- 10 words, dot separator, no number, for a disk-encryption passphrase: cliff.brave.otter.maple.cedar.amber.quill.ocean.ember.quartz, about 76 bits, labeled strong.
- 3 words, underscore, no number, for a quick low-value login: beach_koala_pixel, about 23 bits, weak.
- Default settings (5 words plus a number, hyphens, capitalized): Cedar-Amber-Quill-Otter-Panda-84, about 45 bits, which this tool itself still labels weak.
How diceware entropy is calculated
Each word is chosen independently from the 195-word list, so every word adds log2(195), about 7.6 bits, of entropy. Appending the optional two-digit number adds log2(100), about 6.6 bits, once. Capitalization does not change which word was picked, only its case, so it adds no entropy in this tool's calculation.
- 3 words: 23 bits without a number, 29 bits with one.
- 5 words (default): 38 bits without a number, 45 bits with one.
- 7 words: 53 bits without a number, 60 bits with one.
- 9 words: 68 bits without a number, 75 bits with one.
- 12 words: 91 bits without a number, 98 bits with one.
Recommended word count for a target strength
- To reach ok (50+ bits): at least 7 words without a number, or 6 words with a number appended.
- To reach strong (70+ bits): at least 10 words without a number, or 9 words with a number.
- To reach overkill (90+ bits): 12 words without a number, or 11 words with a number.
- The default of 5 words plus a number is about 45 bits, which this tool itself labels weak. Increase the word count for anything beyond a low-value throwaway login.
Common passphrase mistakes
- Sticking with the default 5 words and assuming that is automatically strong. By this tool's own scale, it is weak.
- Choosing a well-known quote or song lyric instead of independently random words, which defeats the entropy math entirely.
- Skipping the number or a distinct separator because a login form does not require one, then reusing the exact same passphrase everywhere.
- Assuming capitalization adds meaningful entropy. It only changes case, not which word was chosen, so it adds no bits under this tool's estimate.
Frequently asked questions
What is a diceware passphrase?
Diceware is a method of building passphrases by selecting random words from a wordlist. The result is long and memorable yet has well-defined, quantifiable strength.
How many words should I use?
More words means more entropy. Seven or more words without a number, or six with one, reaches this tool's ok threshold; nine to ten words reaches strong. The default of five plus a number is still labeled weak.
Are passphrases as secure as random passwords?
They can be. Security comes from total entropy, so a passphrase with enough words can match or exceed a shorter random password while being much easier to remember.
Does adding a number make it much stronger?
It adds a fixed amount, about 6.6 bits, roughly equivalent to one extra word. Most of the strength still comes from the number of random words, not the appended digits.
Is the passphrase generated privately?
Yes. Words are selected entirely in your browser on your device, and the passphrase is never sent to any server.
What is the difference between this and the password generator?
This tool makes word-based passphrases that are easy to memorize and type, while the password generator makes dense random-character strings. Choose passphrases when you must recall the secret yourself.
What is a diceware generator and how is it different from picking random words myself?
A diceware generator uses a cryptographically secure random source to pick words from a fixed list, the same way this tool uses crypto.getRandomValues. Picking words yourself introduces unconscious bias toward familiar or memorable words, which quietly lowers real-world entropy below what the word count suggests.
How many words do I need for a strong passphrase?
Around nine to ten words without a number, or nine words with one, lands in this tool's strong range above 70 bits. Twelve words reaches overkill.
Does capitalizing the words increase the passphrase's strength?
No. Capitalization only changes the letter case of each word; it does not change which word was picked, so it adds no entropy in this tool's calculation.
Is the default passphrase strong enough for a password manager master password?
Not by this tool's own scale. The default of 5 words plus a number comes out to about 45 bits, labeled weak. For a master password, push the word count up to at least 9 or 10 for a strong result.