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Password Generator

Free secure password generator using Web Crypto API. Adjustable length, character types, entropy analysis, and bulk generation. No sign-up needed. Try now.

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Free Secure Password Generator

Generate cryptographically secure passwords using the Web Crypto API. Customize length, character types, and analyze password strength.

Includes visual strength meter, entropy calculation, brute-force time estimation, and bulk generation of multiple passwords.

Security features

Local cryptographic generation, entropy analysis in bits, brute-force time estimation, support for uppercase, lowercase, numbers, and symbols.

What Makes a Strong Password?

A strong password combines three key factors: length, complexity, and uniqueness. Length is the most important factor: each additional character exponentially multiplies the number of possible combinations. A minimum of 16 characters is recommended for important accounts. Complexity means mixing uppercase letters, lowercase letters, numbers, and special symbols, which vastly expands the search space for an attacker. Uniqueness means never reusing passwords across different services; if one leaks in a data breach, your other accounts remain protected. Avoid dictionary words, proper names, birthdates, or predictable sequences like 123456 or qwerty. Our generator creates random passwords that automatically meet all of these criteria.

Understanding Password Entropy

Entropy measures the unpredictability of a password in bits. The more bits of entropy, the harder it is to crack through brute force. An 8-character password using only lowercase letters has approximately 38 bits of entropy, which a modern computer can break in minutes. Adding uppercase, numbers, and symbols raises the entropy to about 52 bits. Increasing the length to 16 characters with all character types can exceed 100 bits of entropy, which would take billions of years to crack with current technology. Security experts recommend at least 60 bits for general accounts and over 80 bits for critical accounts like online banking or your primary email. Our generator displays the exact entropy of each generated password and estimates the time required to crack it.

Passphrases

An alternative to random passwords is the passphrase: several random words strung together, like "correct-horse-battery-staple". Being long, they reach high entropy, and being made of words, they are easier to remember and type than a string of symbols. The key is that the words be genuinely random, not a meaningful sentence or a well-known quote. For accounts you must memorize, a four or five random-word passphrase usually offers the best balance between security and memorability.

Store Passwords With a Manager and 2FA

Generating strong passwords only helps if you then manage them well. A password manager stores each one encrypted and fills forms for you, so you can use unique, long credentials without memorizing them. Add two-factor authentication (2FA) wherever a service offers it: even if a password leaks, the second factor blocks access. This tool generates passwords in your browser and does not store them; copy them into your manager and do not send them over insecure channels like email or chat.

A worked example

The password generator showing a 16-character password with upper case, lower case, digits and symbols enabled, a strength read-out of 103.4 bits of entropy, and a bulk generator listing further passwords.
Sixteen characters drawn from all four sets gives 103.4 bits of entropy. Read that number for what it is: it measures how many passwords the generator could have produced, so it holds only while the value stays random and unreused. It says nothing about a password you invented yourself, and nothing about one already sitting in a breach corpus.

What this tool did when we measured it

We generated 2,000 passwords of 128 characters with this generator and counted every symbol: 256,000 draws over an 88-symbol alphabet. A uniform source would put 2,909 of each symbol in that sample; we observed between 2,795 and 3,035, a widest gap of 4.3% 2.3 standard deviations, which is ordinary across that many symbols. All 2,000 came out distinct.

Measured on with Chromium 151.0.7922.173. How we measured it

Frequently Asked Questions

Are the passwords truly secure?
Yes, we use the browser's Web Crypto API to generate cryptographically secure passwords with true randomness.
Are passwords stored anywhere?
No, passwords are generated locally and never sent to or stored on any server.
What password length is recommended?
We recommend at least 16 characters with a mix of uppercase, lowercase, numbers, and symbols for maximum security.
What does entropy mean?
Entropy measures password unpredictability in bits. Higher entropy = harder to crack. At least 60 bits is recommended.

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