About this tool
A strong password is the first line of defence for any online account. NIST (National Institute of Standards and Technology) defines a strong password as at least 12–16 characters long drawn from a large character set — combining uppercase letters, lowercase letters, numbers, and symbols. The more characters and the more varied the set, the harder the password is to crack by brute force.
Password entropy measures how unpredictable a password is, in bits. The formula is: Entropy = Length × log₂(Character Set Size). A password using only lowercase letters (26 characters) at 8 characters long has roughly 37.6 bits of entropy. By contrast, a 20-character password using ~94 printable ASCII characters has approximately 131 bits — exponentially harder to crack. This tool displays the entropy of every password it generates.
Passphrases are an alternative to random character strings. Popularised by the Diceware method and the XKCD "correct horse battery staple" comic, a passphrase is a sequence of random words joined by a separator (e.g. "glacier-horizon-cipher-vanguard"). A 4-word passphrase from a 7,776-word list provides ~51.7 bits of entropy; a 6-word passphrase provides ~77 bits — sufficient for most accounts — while being far easier to remember than random characters.
This generator uses the Web Cryptography API (window.crypto.getRandomValues), the cryptographically secure random number generator (CSPRNG) built into every modern browser. Unlike Math.random(), which is a pseudo-random generator unsuitable for security, window.crypto.getRandomValues is designed to be unpredictable. All generation happens locally in your browser — passwords are never sent to any server.
Mistakes to avoid: using personal information (names, birthdays) that can be researched; reusing passwords across sites; using predictable substitutions like p@ssw0rd (well-known to crackers); and using passwords shorter than 12 characters for sensitive accounts. For important accounts (email, banking, password managers), use 20+ characters or a 6-word passphrase, and always enable two-factor authentication.
Practical Usage Examples
Password Generator: Basic Usage
Get started with the Password Generator to see instant, reliable results for your cybersecurity tasks.
Input: [Your cybersecurity Data]
Output: [Processed Result]Step-by-Step Instructions
Choose a generation mode: "Random Characters" for a mixed-character string; "Passphrase" for a sequence of random words; "Hex Token" for API keys.
Set the desired length — for random mode this is character count; for passphrase mode it is word count.
Click "Generate" to create a password using your browser's cryptographically secure random number generator.
Review the entropy score shown — 80+ bits is strong for most accounts; 128+ bits is recommended for master passwords and encryption keys.
Click Copy to copy the password to your clipboard, then paste it directly into your password manager or registration form.
Regenerate as many times as needed — it is instant and free.
Core Benefits
Uses window.crypto.getRandomValues — the browser's cryptographically secure RNG, not Math.random().
Shows entropy in bits so you understand exactly how strong each password is.
100% client-side — passwords are generated in your browser and never transmitted or stored.
Supports random characters, word passphrases, and raw hex tokens for API keys.
Free with no sign-up, no usage limits, and no ads interrupting results.
Frequently Asked Questions
A strong password has high entropy — it is long and drawn from a large character set. NIST recommends at least 12 characters for general accounts and 16+ for sensitive ones. Using uppercase, lowercase, numbers, and symbols together maximises the character set. Critically, it must be random and not contain guessable personal information like names or birthdays.
For most online accounts, 12–16 characters is sufficient. For high-value accounts like email, banking, or password manager master passwords, use 20+ characters or a 6-word passphrase. The longer the password, the exponentially harder it is to crack.
A long passphrase can be as secure as or more secure than a shorter random-character password. A 6-word Diceware passphrase has approximately 77 bits of entropy — stronger than an 8-character mixed-character password (~52 bits). Passphrases have the advantage of being easier to remember while still resisting brute-force and dictionary attacks.
Entropy measures how unpredictable a password is, expressed in bits. It is calculated as Length × log₂(Character Set Size). Higher entropy means more possible combinations. 80 bits is considered strong; 128 bits is very strong for offline attack resistance. This tool calculates and displays entropy for every password it generates.
Yes. This tool uses window.crypto.getRandomValues — the browser's built-in cryptographically secure random number generator. Passwords are generated entirely in your browser and are never sent to any server, stored in a database, or logged. For extra caution with highly sensitive passwords, use the tool in a private browsing window.
Yes. A password manager (such as Bitwarden, 1Password, or KeePass) lets you generate and store a unique strong password for every account without needing to remember them all. Reusing passwords across sites is one of the most common causes of account compromise. A password manager eliminates this risk.
A random password is a string of random characters (e.g. "Kx9@mQ#2pL!v"). A passphrase is a sequence of random words (e.g. "glacier-horizon-cipher-vanguard"). Passphrases are generally easier to type and remember while still offering high entropy when they use 4 or more words from a large wordlist.
Select "Hex Token" mode and set the length to 32 or 64 characters to generate a 128-bit or 256-bit secure random hexadecimal token suitable for use as an API key, session token, JWT secret, or HMAC key.
Once the page has loaded, all generation happens locally using your browser's JavaScript engine and does not require an active internet connection. You can save the page and use it offline.
Yes. This password generator is completely free with no registration, no usage limits, and no premium tier. Generate as many passwords as you need.