Password & Secret Generator
Generate strong passwords, API tokens, and multi-word passphrases with true cryptographic entropy.
Password Entropy & NIST SP 800-63B Guidelines
Password strength is mathematically defined by its information entropy measured in bits ($E = L \times \log_2(R)$), where $L$ is password length and $R$ is character set size.
< 40 Bits Entropy
Very Weak
Cracked in seconds with modern GPUs.
60 - 80 Bits Entropy
Moderate / Good
Sufficient for low-risk online accounts.
> 100 Bits Entropy
Military Grade
Immune to offline brute-force attacks.
Why Use a Password Generator?
Human-created passwords are often predictable and vulnerable to dictionary attacks. A cryptographic password generator uses strong randomness (entropy) to ensure that your passwords, API keys, or WPA3 passphrases cannot be guessed by automated brute-force tools.
Frequently Asked Questions
How is password entropy calculated?
Entropy in bits is calculated as log2(character-set size ^ password length) — a longer password or a larger character set (adding symbols, mixed case) both increase entropy, making the password exponentially harder to brute-force.
Are passphrases more secure than random passwords?
For the same length, a truly random password has higher entropy per character than a passphrase made of dictionary words. However, passphrases (as NIST SP 800-63B recommends) are often more practical since they're easier for humans to remember while still being long enough to resist brute-force attacks.
Why does this tool use window.crypto.getRandomValues instead of Math.random()?
Math.random() is not cryptographically secure and can theoretically be predicted from its outputs. window.crypto.getRandomValues() uses your operating system's cryptographically secure random number generator, which is the standard required for generating passwords, tokens, and keys.
Is it safe to generate my password on a website?
Yes, in this case — generation happens entirely in your browser via the Web Crypto API, and the password is never transmitted to any server or logged anywhere.
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