Is this password generator secure?

Yes. It uses the Web Crypto API for cryptographic randomness and runs entirely in your browser. No passwords are sent to any server or stored anywhere.

How long should my password be?

At least 12 characters for most accounts, 16+ for sensitive accounts. Longer passwords with mixed character types are exponentially harder to crack.

What is password entropy?

Entropy measures password randomness in bits. Higher entropy = harder to crack. 80+ bits is very strong. The formula is length × log2(character pool size).

Password Generator

Generate strong, random passwords using cryptographic randomness. Customize length and character types. Nothing is sent to any server — your password is generated entirely in your browser.

How the Password Generator Works

This password generator uses the Web Crypto API, the same cryptographic engine that secures banking websites and encrypted messaging apps. When you click generate, the browser produces truly random bytes using hardware-level entropy sources, then maps each byte to a character from your selected pool. The entire process runs locally in your browser — no password is ever transmitted to a server, stored in a database, or logged anywhere. You can verify this by disconnecting from the internet and generating passwords offline. The tool also calculates entropy, a measure of randomness expressed in bits, so you can objectively assess the strength of each generated password.

Password Entropy Formula

Entropy (bits) = Length × log₂(Character Pool Size)

Pool sizes: lowercase = 26, +uppercase = 52, +digits = 62, +symbols = ~90 characters

What Makes a Strong Password

Password strength depends on three factors: length, character diversity, and randomness. Length is the most important — a 16-character password with only lowercase letters (77 bits of entropy) is stronger than a 10-character password using all character types (65 bits). Adding uppercase letters, numbers, and symbols increases the character pool, making each position harder to guess. Crucially, the password must be truly random. "P@ssw0rd123!" includes all character types but is among the first combinations attackers try. Avoid dictionary words, names, dates, keyboard patterns like "qwerty," and common substitutions like @ for a. A randomly generated password like "k7$Bm2!xQpL9vR" is exponentially harder to crack than any human-chosen password of the same length.

Password Security Best Practices

Use a unique password for every account. If one service suffers a data breach, reused passwords give attackers access to all your other accounts. A password manager stores and autofills unique passwords so you only need to remember one master password. Enable two-factor authentication (2FA) wherever available — even if an attacker obtains your password, they cannot log in without the second factor. Prefer authenticator apps or hardware keys over SMS-based 2FA, which is vulnerable to SIM swapping. Change passwords immediately if a service reports a breach. Never share passwords via email or messaging apps. For your most critical accounts — email, banking, and cloud storage — use passwords of at least 16 characters generated by this tool and stored securely in your password manager.