Passphrase Generator
Password & SecurityProcessed locally in your browser using the Web Crypto API. Nothing is sent to any server.
How It Works
This tool generates Diceware-style passphrases by randomly selecting words from the EFF (Electronic Frontier Foundation) large wordlist, which contains 7,776 carefully chosen English words.
How It Works
- Wordlist: EFF large wordlist (7,776 words, ~12.9 bits of entropy per word)
- Randomness: Uses
crypto.getRandomValues()for cryptographically secure random selection - Uniform distribution: Each word has an equal chance of being selected, ensuring maximum entropy
- Entropy calculation: Total entropy = number of words × 12.9 bits per word
Entropy by Word Count
- 4 words ≈ 51.7 bits — acceptable for low-risk accounts
- 5 words ≈ 64.6 bits — strong for most purposes
- 6 words ≈ 77.5 bits — very strong
- 7+ words ≈ 90+ bits — extremely strong, resistant to any foreseeable attack
Options
- Separator: Choose between hyphen (-), space, period (.), underscore (_), comma (,), or no separator
- Capitalize: Capitalize the first letter of each word (adds ~0.3 bits per word)
- Include Number: Append a random digit (0-9) to each word for extra complexity
- Include Symbol: Append a random symbol (!@#$%^&*) to each word for maximum security
- Quantity: Generate up to 10 passphrases at once
How to Create a Strong Passphrase
- Use at least 5 words: More words exponentially increase security. Aim for 6-7 words for sensitive accounts.
- Enable capitalization: Adds complexity without sacrificing memorability.
- Consider adding numbers or symbols: Boosts entropy further, especially for high-security accounts.
- Use a unique passphrase per account: Never reuse passphrases across different services.
- Store securely: Use a password manager to store your passphrases safely.
Frequently Asked Questions
What is a passphrase?
A passphrase is a password made of multiple random words, like "correct-horse-battery-staple". Passphrases are easier to remember than random character strings while providing comparable or better security.
What wordlist is used?
The EFF (Electronic Frontier Foundation) large wordlist containing 7,776 common English words. Each word provides approximately 12.9 bits of entropy.
How many words should I use?
At least 5 words for strong security (64+ bits of entropy). For maximum security, use 7 or more words. More words = exponentially harder to crack.
Are passphrases stored or sent anywhere?
No. Everything runs in your browser. Generated passphrases are never stored, logged, or transmitted.
Passphrase vs password — which is better?
Passphrases are easier to remember and type manually, making them ideal for master passwords or accounts you access frequently. Random character passwords are better for accounts stored in a password manager. Both can be equally secure if long enough.
How often should I change my passphrase?
Only change it if you suspect it has been compromised. Modern security guidance (NIST) recommends against routine password rotation unless there is evidence of a breach.
Privacy Note
This tool runs entirely in your browser. Your input is never uploaded, stored, or sent to any server.
Disclaimer: This tool is provided for educational and informational purposes only. The results do not constitute professional security advice. Use at your own discretion.