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Strong password generator

Create strong, random passwords with the length and character types you choose. Generated in your browser — nothing is sent.

Your password
_yc=%SIGF@#$dpbD
StrengthVery strong · ~99 bits
Guide How to create a strong password Interactive lesson: How long to crack your password That 8-character password with a symbol falls in 9 hours. See why 12 plain lowercase letters are 14× stronger.

How the calculation works

The password is built by drawing characters from the set you enabled (lowercase + optional uppercase, numbers and symbols), all in your browser. "Strength" estimates entropy: length × log₂(set size). Above ~60 bits is considered strong.

Examples

  • A 16-char password with letters, numbers and symbols has ~100 bits of entropy (very strong).
  • Lowercase only, 8 chars: ~37 bits — weak for important accounts.

Frequently asked questions

Is the password sent to any server?

No. It is generated 100% in your browser and never leaves your device.

What length should I use?

Use 16+ characters with several types. The longer and more varied, the harder to crack.

Do I need to memorize every password?

No — use a password manager to store long, unique passwords. You only memorize the master password.

Long password or complex password?

Long. Twelve lowercase letters are about 14 times stronger than eight characters with symbols.

Are passphrases really secure?

Yes, if the words are genuinely random. Six random words from a ~7,776-word list give about 2.2 × 10²³ combinations.

Should I rotate passwords periodically?

Not without cause. Scheduled rotation was dropped because it leads to predictable variations.

Is the generated password sent to a server?

No. It is generated in your own browser using the system cryptographic randomness and never leaves your device.

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Updated on June 30, 2026 · by Rafael Rossi · Methodology & sources