Password Generator
Generate strong, secure passwords instantly. Customize length and character types. All generation happens in your browser — nothing is sent to any server.
Part of our Math & Percentage Calculators collection.
Password Generator
Free online calculator
How to Use This Calculator
- 1
Set your desired password length (16+ is recommended).
- 2
Choose which character types to include.
- 3
The password generates automatically — click Calculate to regenerate.
- 4
Copy the password and save it in a password manager.
Password Security & Entropy
Password entropy (bits) = log₂(charset_size ^ length) Charset sizes: Lowercase only: 26 chars Lower + Upper: 52 chars Lower + Upper + Numbers: 62 chars All (+ symbols): ~94 chars A 16-character password with all char types has ~105 bits of entropy — effectively uncrackable with current technology.
Example Calculation
Example: 16-character password, all character types
Inputs
length: 16includeUpper: yesincludeLower: yesincludeNumbers: yesincludeSymbols: yes
Result
e.g. K#7mP$2xQw!nL9vR
16 characters from a ~94-character set gives ~105 bits of entropy. This would take billions of years to crack by brute force.
Frequently Asked Questions
How long should my password be?
At minimum 12 characters for most accounts. For high-value accounts (banking, email, work), use 16–20 characters. Length matters more than complexity.
Is this password generator safe to use?
Yes. All password generation happens in your browser using JavaScript. Nothing is transmitted to any server. We never see or store your generated passwords.
Should I use a password manager?
Absolutely. A password manager lets you use a unique, strong password for every account without memorising them. LastPass, 1Password, Bitwarden, and your browser's built-in manager are all solid options.