A passphrase is a sequence of random words joined together. Because each word is chosen from a large dictionary using a cryptographically secure random number generator, a four-word passphrase is significantly harder to guess than a typical 8-character password — while being much easier to remember.
All generation happens in your browser. No passphrase is ever sent to a server.
| Number of words | More words means a stronger passphrase. Four words or more is recommended for anything important. |
| Numbers | Replaces one letter per word with a look-alike digit: a→4, e→3, l→1, s→5, and others. |
| Symbols | Replaces one letter per word with a symbol: a→@, s→$, i→!, o→*. |
| Capitals | Randomly capitalises one letter per word. |
This generator is also available as a Model Context Protocol server, so AI assistants such as Claude can call it as a tool directly.
Tools available via MCP:
generate_passphrase — generate a single passphrasegenerate_multiple_passphrases — generate a batch to choose fromlist_word_lists — discover available word listsSource and deployment instructions: github.com/timothyohare/passphrasegenerator