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Password Strength Checker

Test your password strength and get improvement recommendations. Privacy-first, client-side processing - your password never leaves your browser.

Privacy Notice: Strength analysis happens in your browser. We never log or store your password.

Password Policy Checker

NIST Password Guidelines (SP 800-63B)
These guidelines are from the National Institute of Standards and Technology (NIST) Digital Identity Guidelines.

What Organizations SHOULD Do

  • Minimum Length: Require at least 8 characters for user-chosen passwords, 6 for machine-generated
  • Maximum Length: Allow at least 64 characters
  • All Characters: Accept all printable ASCII characters, including spaces
  • Unicode: Support Unicode characters (emojis, international characters)
  • Breach Checking: Compare passwords against lists of commonly used, expected, or compromised passwords
  • Rate Limiting: Limit failed authentication attempts (to prevent brute force)
  • Show Password Option: Offer option to display the password while typing
  • Password Managers: Allow paste functionality (don't block password managers)

What Organizations SHOULD NOT Do

  • Composition Rules: Don't impose arbitrary complexity requirements (e.g., "must include uppercase, number, and special character")
  • Password Expiration: Don't require periodic password changes without evidence of compromise
  • Password Hints: Don't use knowledge-based authentication (e.g., "What is your mother's maiden name?")
  • SMS 2FA: Don't use SMS as two-factor authentication (use authenticator apps or hardware tokens instead)
  • Truncation: Don't silently truncate passwords

Key Principles

Length Over Complexity:

A longer password (e.g., "correct horse battery staple") is generally more secure than a shorter complex one (e.g., "P@ssw0rd!").

User-Friendly Security:

Complex rules frustrate users and often lead to predictable patterns (e.g., "Password1!", "Password2!").

Focus on Compromise Detection:

Check passwords against breach databases rather than forcing arbitrary complexity.

Enable Multi-Factor Authentication:

MFA is more effective than complex password requirements for security.

Password Security Tips

  • Use a password manager to generate and store unique passwords
  • Create passphrases with 4-5 random words (e.g., "correct-horse-battery-staple")
  • Never reuse passwords across different sites
  • Enable two-factor authentication (2FA) whenever available
  • Avoid personal information (names, birthdays, addresses)
  • Change passwords immediately if a service reports a breach

Need Help with Password Policies?

Our security team can help you implement robust password policies and multi-factor authentication across your organization.

Frequently Asked Questions

Common questions about the Password Strength Checker

A strong password combines length (12+ characters minimum), complexity (uppercase, lowercase, numbers, symbols), and unpredictability. Avoid dictionary words, personal info, common patterns like "123456" or "qwerty", and sequential characters. The most important factor is length - each additional character exponentially increases cracking difficulty.

⚠️ Security Notice

This tool is provided for educational and authorized security testing purposes only. Always ensure you have proper authorization before testing any systems or networks you do not own. Unauthorized access or security testing may be illegal in your jurisdiction. All processing happens client-side in your browser - no data is sent to our servers.

Password Strength Checker - Free Online Tool | Inventive HQ