Strong Password Generator – Free Random Secure Password Maker
Create strong, random, and secure passwords instantly. Customize length and character types — uppercase, lowercase, numbers, and symbols. All generation happens in your browser using cryptographic-grade randomness.
What Is the Password Generator?
The Password Generator is a free online tool that creates strong, random, and secure passwords using cryptographic-grade randomness. You can customize the length and choose which character types to include — uppercase letters, lowercase letters, numbers, and symbols — to meet any website's password requirements.
Every password is generated locally in your browser using the Web Crypto API (crypto.getRandomValues), which provides cryptographically secure random numbers. Your passwords are never transmitted, stored, or shared.
How to Use the Password Generator
Creating a strong password takes just a few steps:
- Set the length. Drag the slider to choose a password length from 4 to 64 characters. Longer passwords are exponentially harder to crack.
- Select character types. Check the boxes for uppercase, lowercase, numbers, and symbols. At least one type must be selected.
- Exclude ambiguous characters (optional). Tick this to remove easily-confused characters like 0, O, l, 1, and I.
- Click “Generate Password”. A new random password appears instantly in the display box.
- Copy the password. Click the “Copy” button to copy it to your clipboard, ready to paste wherever you need it.
How Does the Password Generator Work?
The tool uses a layered character pool with a cryptographically secure shuffle algorithm. Here is what happens behind the scenes when you click Generate:
Cryptographic Randomness
Unlike Math.random(), which is not suitable for security purposes, this tool uses the crypto.getRandomValues() function from the Web Crypto API. This function is designed for cryptographic use and provides true random values backed by the operating system's entropy source.
Layered Character Pool
The generator builds a character pool from your selected categories (uppercase, lowercase, numbers, symbols). It then ensures at least one character from each selected category is included, so the password always contains the character types you chose. The remaining slots are filled with random picks from the full pool, and the entire password is then shuffled for maximum randomness.
Strength Rating
The strength meter evaluates your password based on two factors: length and character variety (the number of distinct character types enabled). The rating uses an entropy-based scoring system:
- Very Weak — under 40 bits of entropy (typically short, single-type passwords).
- Weak — 40–59 bits.
- Fair — 60–79 bits.
- Strong — 80–119 bits.
- Very Strong — 120 bits or more.
Entropy is calculated as length × log2(poolSize). A 16-character password using all four character types has a pool of 94 characters, yielding about 104 bits of entropy — strong enough to resist brute-force attacks for the foreseeable future.
Batch Generation
Need multiple passwords at once? Use the batch dropdown to generate 1, 5, 10, or 20 passwords simultaneously. Each password is independently random and can be copied individually or all at once.
100% Private — Passwords Never Leave Your Browser
Every password is generated entirely on your device. No password is ever sent to a server, stored in a database, or logged anywhere. This makes the tool safe to use even for your most sensitive accounts.
Key Features
- Cryptographic security — uses the Web Crypto API for true randomness, not pseudo-random.
- Adjustable length — from 4 to 64 characters.
- Four character types — uppercase, lowercase, numbers, and symbols.
- Ambiguous character exclusion — remove 0, O, l, 1, I for better readability.
- Real-time strength meter — entropy-based rating from Very Weak to Very Strong.
- Batch generation — create up to 20 passwords at once.
- One-click copy — copy individual passwords or all at once.
- 100% client-side — no data is ever uploaded or stored.
- Fully responsive — works on desktop, tablet, and mobile.
Tips for Strong Passwords
- Use at least 16 characters. Every additional character exponentially increases cracking time.
- Enable all four character types. A mix of uppercase, lowercase, numbers, and symbols maximizes entropy.
- Never reuse passwords. Use a unique password for every account. Consider a password manager to store them.
- Enable two-factor authentication wherever possible for an extra layer of security.
- Avoid personal information — names, birthdays, and common words are easy to guess.
Frequently Asked Questions
Is this password generator safe to use?
Yes. All passwords are generated locally in your browser using the Web Crypto API (crypto.getRandomValues), which provides cryptographically secure randomness. Your passwords are never transmitted over the internet or stored on any server.
How long should my password be?
We recommend at least 16 characters for most accounts. A 16-character password using all four character types (uppercase, lowercase, numbers, symbols) provides approximately 104 bits of entropy, which is considered very strong and resistant to brute-force attacks.
What makes a password strong?
Two factors: length and character variety. The longer the password and the more character types it uses, the higher its entropy. Entropy is measured in bits — the higher the bits, the harder the password is to crack. Aim for at least 80 bits (Strong) or higher.
Are the generated passwords truly random?
Yes. The tool uses crypto.getRandomValues(), which is designed for cryptographic use and draws from the operating system's entropy source. This is far more secure than Math.random(), which is predictable and not suitable for security.
Does this tool store my passwords?
No. All generation happens in your browser. Passwords are not uploaded, stored, logged, or shared with anyone. Once you navigate away or close the tab, the generated passwords are gone.
Can I generate multiple passwords at once?
Yes. Use the “Batch generate” dropdown to create 1, 5, 10, or 20 passwords simultaneously. Each password is independently random. You can copy them individually or all at once using the “Copy All” button.
Can I use this password generator on mobile?
Absolutely. The tool is fully responsive and works smoothly on phones, tablets, and desktops. The interface adapts to smaller screens for easy use on any device.