Generate StrongUnbreakable Passwords

Our password generator uses the Web Crypto API (crypto.getRandomValues) — the same cryptographic randomness used by browsers for encryption. You configure length, character sets, and options, and the tool generates truly random passwords directly in your browser. No passwords are ever sent to or stored on any server.

A strong password has two key properties: length and character diversity. Each additional character exponentially increases the possible combinations. Using uppercase, lowercase, numbers, and symbols creates a larger character pool. Our entropy meter shows exactly how many bits of security your password provides. Aim for at least 60 bits (shown as "Strong") for most accounts, and 80+ bits for sensitive accounts.

Entropy is a mathematical measure of password unpredictability, expressed in bits. Each additional bit of entropy doubles the number of possible passwords an attacker must try. For example, 40 bits means 2^40 (about 1 trillion) possible combinations. NIST recommends at least 112 bits for high-security applications, which our tool can easily achieve with 20+ character passwords.

Passphrases offer a great balance between security and usability. A 4-word passphrase from a 100-word list provides about 26 bits of entropy per word, totaling ~104 bits — comparable to a 16-character random password with all character sets. Passphrases are easier to remember and type, making them ideal for master passwords, WiFi credentials, and situations where you need to manually enter them.

Excluding similar characters (i, l, 1, L, o, 0, O) reduces the character pool slightly but makes passwords much easier to read aloud or type on mobile keyboards. This is especially useful for passwords you need to share verbally or enter on devices with small screens. The entropy loss is minimal — typically less than 2 bits for a 20-character password.

We calculate cracking time using industry-standard assumptions: online attacks at 1,000 guesses per second (throttled by servers), offline fast hash attacks at 1 billion guesses per second (using GPUs), and offline slow hash attacks at 10,000 guesses per second (using bcrypt/argon2). The displayed time reflects the online attack scenario as a conservative estimate.

Yes — our tool is completely safe. All processing happens client-side using JavaScript. We never send any data to a server, never use cookies for tracking, and never log anything. The Web Crypto API provides true random values from the operating system's entropy source. For maximum security, you can disconnect from the internet while using the generator.

Yes! Once the page loads, the entire password generator works completely offline. You can disconnect from the internet and continue generating passwords. All computation — including cryptographic random number generation, entropy calculation, and strength analysis — happens locally in your browser.