Passphrase Generator

Generate cryptographically strong, easy-to-remember word-based passphrases using Diceware. Choose custom separators, casing, and alphanumeric filters.

Passphrase Settings

6

Generated Passphrase

Strength: Strong62.0 bits of entropy
Individual WordsClick any card to re-roll just that word

How the Diceware Passphrase Generator Works

A Passphrase is a security credential made up of multiple complete dictionary words separated by spaces or punctuation (e.g. correct-horse-battery-staple). This differs from standard character-based passwords (like j*8%A9!w), which are extremely difficult for humans to memorize.

This tool uses the Diceware method to construct memorable, cryptographically strong passphrases. It processes all calculations locally in your browser using the web’s native cryptographic APIs.

🎲 The Mathematical Security of Diceware

In classical Diceware, a user rolls a 6-sided die five times to generate a five-digit code (e.g. 2-3-4-1-6). This code is then matched to a specific word on a printed list of 7,776 words.

This generator automates this process by selecting words from a curated list of 1,296 readable English words ($6^4$ layout) using the browser’s built-in cryptographic randomizer.

Entropy Calculation Formula

To determine the strength of your passphrase, we calculate Shannon Entropy in bits:

$$\text{Entropy (bits)} = N \times \log_2(\text{wordlist size})$$

  • For a 1,296 wordlist, each word provides $\log_2(1296) \approx 10.34$ bits of entropy.
  • A 6-word passphrase provides $6 \times 10.34 = 62.0$ bits of entropy.
  • If you inject numbers or symbols, the character search space increases, which adds extra security bits.

According to modern security standards:

  • Less than 40 bits: Very Weak. Can be cracked instantly.
  • 40 to 55 bits: Medium. Good for secondary accounts.
  • 55 to 75 bits: Strong. Excellent for personal logins and master passwords.
  • 75+ bits: Excellent. Highly resistant to brute-force cracking.

Key Settings & Instructions

  • Number of Words: Use the slider to select from 3 to 12 words. Modern security standards recommend at least 5 words for basic logins and 6+ words for critical keys.
  • Word Separators: Choose how words are connected: space, hyphen, underscore, period, or concatenated directly.
  • Individual Word Re-roll: Click on any single word card to swap or re-roll only that word. This is useful if a generated word is hard for you to remember or type.
  • Modifiers: Check the Alphanumeric options to inject random numbers or symbols inside the words to satisfy old-fashioned system password requirements.

Frequently Asked Questions (FAQ)

Are my generated passphrases sent to any server?

No. This tool processes all calculations locally in your browser. No words, lists, configurations, or generated passphrases are ever uploaded to DwellixTools servers, keeping your data private.

What random generator does this tool use?

This tool uses the browser’s Web Crypto API (window.crypto.getRandomValues) to fetch cryptographically strong, unpredictable random numbers. This ensures that the generated values are secure and not predictable by mathematical patterns.

Why are passphrases better than traditional passwords?

Passphrases offer high entropy (security) while remaining easy for humans to read, type, and memorize. A 6-word passphrase is significantly harder for a computer to guess via brute force than a short random string, but it takes less effort to type on mobile keyboards.

Can I copy individual words from the passphrase?

Yes. You can review each word in the “Individual Words” section at the bottom and copy them individually or click them to re-roll them if they don’t suit you.

For master keys, password managers, or financial accounts, we recommend a length of at least 6 words combined with custom separators, providing over 60 bits of entropy.