Generate a strong, memorable, word-based passphrase using the Diceware method, ideal as a master password.
The Diceware method, originally proposed by security researcher Arnold Reinhold, generates passphrases by randomly selecting words from a large, fixed word list, traditionally using physical dice rolls to pick each word. This Passphrase Generator applies the same core principle using your browser's cryptographically secure random number generator instead of dice, producing memorable, word-based passphrases that are often significantly easier to recall and type accurately than an equivalent-strength string of random characters.
Every word is chosen entirely locally using the Web Crypto API's random number generator, and nothing about the passphrase you generate is transmitted, logged, or stored anywhere outside your own browser session.
Human memory is generally much better at recalling a short sequence of ordinary words than an equivalent-length string of random letters, numbers, and symbols. A five-word passphrase drawn randomly from even a modest word list can have comparable or greater entropy than a much shorter fully-random character string, while remaining dramatically easier to type correctly and memorize over time, especially for something like a master password you'll need to enter regularly, such as the one protecting our Local Password Vault tool.
Each word you add to the passphrase multiplies the total number of possible combinations by the size of the word list used. This tool calculates and displays the resulting entropy in bits based on the actual word list size and number of words selected, giving you a concrete, honest measure of the passphrase's real strength rather than just an intuitive sense that "more words feels stronger." As a general guideline, five or more randomly selected words from a reasonably sized list provides strong protection suitable for a master password protecting other secrets.
Different systems have different requirements for what a valid password can contain. This tool lets you choose a separator between words (a hyphen, a space, a period, or none at all), optionally capitalize each word, and optionally append a random number, letting you meet a specific site's character requirements while preserving the underlying word-based structure that makes the passphrase memorable in the first place.
Our standard Password Generator produces fully random character strings, which offer excellent entropy density but can be genuinely difficult to memorize or type accurately without a password manager's autofill. This Passphrase Generator trades a small amount of entropy density for dramatically improved memorability, making it particularly well suited for the small number of passwords you genuinely need to type from memory regularly, such as a device unlock passphrase or a password manager's own master password, while random character passwords remain the better default for everything a password manager stores and autofills on your behalf.
The original Diceware technique involved physically rolling five six-sided dice to generate a five-digit number, then looking that number up in a published word list to select a single word, repeating the process for each word in the final passphrase. This browser-based generator captures the same underlying randomness guarantee using a cryptographically secure random number generator instead of physical dice, while remaining just as transparent about exactly how each word gets chosen.
Consider pairing a generated passphrase with a small, personal modification only you know, such as inserting a familiar number in a fixed position, which can add a further layer of protection against any generator-specific word list becoming a target of dedicated attacks, though a sufficiently long, unmodified passphrase from this tool already offers strong protection on its own.
It can be, depending on the number of words and the size of the word list. This tool calculates and displays the actual entropy so you can compare it directly to an equivalent-strength random password.
Passphrases work especially well for passwords you need to type from memory regularly, like a device unlock code or a password manager's master password, since they're much easier to recall accurately.
No, every word is selected locally using your browser's cryptographically secure random number generator. Nothing is transmitted or logged.
Each additional word multiplies the total number of possible combinations by the size of the word list, meaningfully increasing entropy with each word added.
For anything stored and auto-filled by a password manager, a fully random password remains the stronger default. Reserve passphrases for the few passwords you genuinely need to type from memory.
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