Free Secure Password & Passphrase Generator
Generate strong random passwords and Diceware-style passphrases locally in your browser. Uses the standard Web Crypto API, includes entropy feedback, and sends nothing to a server.
Made by Mr Binary SniperPassword Settings
Entropy & Security Metrics
Generated Results
Why is Password Entropy Important?
Entropy is a mathematical measure of the unpredictability or randomness of a password. In cybersecurity, it is measured in **bits**. The higher the entropy value, the harder a password is to brute-force or guess.
Guessed within seconds by basic cracking engines. Avoid for any real account.
Suitable for low-risk online accounts, but vulnerable to customized GPU dictionary attacks.
Highly secure. It would take modern computing clusters millions of years to decipher.
Perfect cryptographic grade security. Exceeds standard defense system requirements.
Passwords vs. Passphrases: Which Should You Choose?
Option A: Cryptographic Password
Made of dense, completely random character sets containing numbers, capital letters, and symbols (e.g. 9k$fL@7#pP!qW).
- Best for machines, API keys, WiFi settings, and systems that restrict character types.
- Nearly impossible to remember; requires a password manager.
Option B: Multi-word Passphrase
Uses a sequence of random dictionary words (e.g. apple-bee-milk-gray). This uses the **Diceware** method.
- Best for main login keys, laptop passcodes, and master passwords.
- Highly secure due to length, yet easy for humans to type and recall.
Frequently Asked Questions
Are my generated passwords sent to a server?
No. Passwords and passphrases are generated locally in your browser with client-side JavaScript. Generated values are not uploaded, logged, or sent to a server.
How does the Web Crypto API make passwords secure?
Standard JavaScript Math.random() is not suitable for passwords because its output can be predictable. This tool uses window.crypto.getRandomValues(), a cryptographically secure browser API designed for stronger random values.