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Password Generator

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Batch Generate

📖 About Password Security

Weak (Entropy < 40 bits)

Easily cracked by brute force, usually all digits or very short passwords.

Medium (Entropy 40–59 bits)

Basic security, but not suitable for protecting important accounts; increasing length is recommended.

Strong (Entropy 60–79 bits)

Suitable for most scenarios with good resistance to cracking.

Very Strong (Entropy ≥ 80 bits)

High security level, recommended for important accounts and encryption keys.

Password EntropyThe core metric for measuring password strength:Entropy = log₂(character set size ^ password length)

  • The larger the character set (uppercase + lowercase + numbers + symbols), the higher the entropy per character.
  • The longer the password, the higher the total entropy, making cracking exponentially harder.
  • This tool uses the browser's built-in crypto.getRandomValues password generator for stronger randomness.
  • Passwords are never uploaded to the server; everything is done locally.

⚠️ Recommendations:For important accounts, use passwords with length ≥ 16, including uppercase, lowercase, numbers, and symbols, and use a password manager.