Password Phrase Generator
Build memorable multi-word passphrases with live entropy in bits.
What this tool does
A password phrase generator joins random words into a single passphrase - 'correct-horse-battery-staple' in the famous example - and this one shows the entropy in bits as you adjust the word count. Passphrases get their strength from length and randomness together: four random words from the bundled list carry about 40 bits, six carry about 60, and adding words adds strength linearly where adding characters to a short password quickly does not. Everything is generated in the browser from a bundled list; nothing is fetched or sent.
Builds a memorable multi-word passphrase from a bundled word list, with word count and separator controls.
Shows the entropy in bits as you adjust the words, so strength is visible rather than assumed.
Formats for URL safety and offers capitalisation and number insertion without hiding the result.
Generates entirely in the browser with the cryptographic random source, never fetching a list.
How to use it
- Choose how many words you want - six is a solid default.
- Pick a separator: hyphen, space, dot or none.
- Optionally add a capitalisation pattern or a number.
- Read the entropy figure in bits before accepting the result.
- Copy the passphrase and store it in a password manager.
Why use this tool
A password phrase generator produces passwords that are both stronger and easier to type than the usual mix of symbols, because the strength comes from how many random words are joined rather than from character-class gymnastics. A passphrase of six random words survives brute force at rates that would take a short complex password geological time, and it can still be remembered after a week - which is the property that stops it being written on a sticky note.
Why we built it
We built this password phrase generator to show the entropy in bits live, because the number is the whole argument and every passphrase generator that hides it asks for trust instead. The word list is bundled into the page, so generation works offline and no request reveals that you are making a password at all - fetching a word list from a server would be the one thing a password tool must never do. The random password generator covers character-based passwords and the password strength checker rates an existing password.
For the word source itself, the random word generator draws from the same kind of list without the passphrase framing.
Who this tool is for
- Anyone replacing short complex passwords with something stronger
- People who must remember passwords without a manager
- Teams needing a shared secret that can be spoken aloud
- Anyone wanting to see the entropy figure before trusting a passphrase
When to use it
- Creating a master password for a new password manager.
- Replacing a reused password on an important account.
- Setting a Wi-Fi password guests can type.
- Generating a shared team secret that must be readable aloud.
How it is calculated
Each word is drawn uniformly at random from the bundled list using the browser's cryptographic random source. Entropy is words × log2(list size): the bundled list of just over a thousand common words carries just over 10 bits per word, so six words give about 60 bits. Separators and capitalisation add formatting, not entropy - the strength comes from the word count. Adding digits or caps is fine for sites that demand them, but the words are the load-bearing part.
Worked example: six words at just over 10 bits each gives about 60 bits of entropy - roughly 10^18 combinations. At a billion guesses a second that is about three decades of work; eight words at 80 bits pushes the same calculation into the millions of years.
Strength assumes the words are drawn independently and uniformly at random. Never pick words yourself, never reuse a passphrase across sites, and store it in a password manager - memorability is a bonus, not the storage plan.
How many words is enough
| Words | Entropy | Verdict |
|---|---|---|
| 3 | 30 bits | Weak by modern standards |
| 4 | 40 bits | Minimum for low-value accounts |
| 6 | 60 bits | Solid for most accounts |
| 8 | 80 bits | Strong - master password territory |
| 10 | 100 bits | Excessive, and still typeable |
Four words was the famous example; six is the modern default, and eight for anything guarding everything else.
A worked example
These are the settings the generator opens with, so you can see how a passphrase is put together. Change any setting on the page and a fresh phrase is generated; the figures below describe the default arrangement.
| Setting | Value |
|---|---|
| Words | 6 |
| Separator | Hyphen |
| Entropy | 60 bits |
With those settings, the generator returns a phrase like:
- correct-horse-battery-staple-anvil-meadow
- About 60 bits of entropy from 6 independently drawn words
- Typeable, speakable, and memorable after a few uses
- Adding two more words raises it to about 80 bits
What you enter, and what you get back
| Item | Details |
|---|---|
| Words and separator | How many words, and how they join. |
| Formatting | Optional capitals and a trailing number. |
| Result | The passphrase, its entropy in bits, and its word count. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| Site rejects the phrase | Password field demands a symbol or cap. | Add the number or capitals option - the words carry the strength. |
| Phrase feels unmemorable | Too many words at first. | Start at six; the phrase settles after a few uses. |
| Words hard to spell aloud | Separatorless words blur together. | Use hyphens or dots - they cost no entropy. |
| Same phrase everywhere | One strong password reused. | Generate a fresh phrase per site; a manager remembers them. |
Assumptions and limitations
- Entropy assumes independent uniform draws from the bundled word list - never pick words yourself.
- Formatting options (capitals, numbers) satisfy site rules but add no real entropy.
- The passphrase is generated in the page and shown on screen - use it somewhere private.
- A passphrase is only as safe as where it is stored; a password manager remains the right home.
Frequently asked questions
What is a passphrase versus a password?
A password is typically a short mix of characters - 'Tr0ub4dor&3' - while a passphrase joins several random words, like 'correct-horse-battery-staple'. Passphrases gain strength from length and word count, which makes them both stronger and far easier to remember than short complex passwords.
How many words should a passphrase have?
Six words from the bundled list gives about 60 bits of entropy, which is solid for most accounts; use eight (about 80 bits) for a master password guarding everything else. Three or four words is below modern recommendations.
What is a diceware passphrase?
Diceware is the method of rolling dice to pick words at random from a list, producing a passphrase with measurable entropy. This generator does the same thing with the browser's cryptographic random source instead of dice - the principle is identical, the uniformity is easier to guarantee.
Are word passphrases safe to use?
Yes, when the words are drawn randomly and each site gets its own phrase. Six random words carry roughly 60 bits of entropy, which resists brute force at rates that would break a short complex password instantly. The risks are reuse and writing it down - use a manager.
How is passphrase strength measured?
In bits of entropy: words × log2(word list size). The bundled list of just over a thousand common words carries just over 10 bits per word, so six words give about 60 bits and eight about 80. Each extra bit doubles the work an attacker faces; the generator shows this figure live as you change the word count.
Can I customise the separator?
Yes - hyphen, space, dot or no separator at all. The separator costs no entropy, since strength comes from the words themselves; choose whatever makes the phrase easiest for you to type and read aloud.