What Is Password Entropy and How Is It Measured?
Entropy is the measure of randomness and unpredictability in a password, expressed in bits. The formula is E = L * log2(R), where L is password length and R is the character pool size (uppercase, lowercase, numbers, symbols).
A 16-character password using all four character sets provides over 105 bits of entropy. At 100 billion guesses per second, cracking such a password would require over 10 million years.
Why You Should Never Use Insecure Math.random() Functions
Many free online password generators use JavaScript's built-in Math.random() function, which is a pseudo-random number generator (PRNG) with predictable internal states. An attacker observing past outputs can predict future generated passwords.
DocSwift uses the browser Web Crypto API (crypto.getRandomValues), which sources hardware-level entropy directly from your operating system kernel (such as /dev/urandom on Unix or CryptGenRandom on Windows).
Step-by-Step Tutorial
Select Minimum 16+ Characters
Set password length to at least 16 to 24 characters for master passwords and server SSH keys.
Enable Character Variations
Include uppercase, lowercase, numbers, and high-entropy special symbols.
Copy Directly to Password Manager
Copy the generated password directly into your secure vault (1Password, Bitwarden, or KeePass).
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Frequently Asked Questions
Can DocSwift see or store my generated passwords?
Never. Generation occurs entirely within your local device RAM using Web Crypto. When you close the tab, all memory is wiped.
What is considered a safe bit-entropy score?
Any password exceeding 80 bits of entropy is considered cryptographically secure against online and offline attacks.