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Password Strength Checker

100% Client-Side

Test password strength, cryptographic entropy bits, and estimated brute-force crack times locally in your browser. Zero data leaves your device.

Enter Password to Test

Strength: Very Strong 90 / 100

Entropy: 64 bits

Length: 16 chars

Crack Time: Centuries

Security Checklist

⚪ Minimum 12 characters

⚪ Lowercase letters (a-z)

⚪ Uppercase letters (A-Z)

⚪ Numbers (0-9)

⚪ Symbols (!@#$%^&*)

⚪ No common passwords

How to Use Password Strength Checker

Enter Password

Type any test passphrase or generate a random high-entropy key.

Inspect Security Rating

Review real-time score out of 100, entropy bits, and crack time estimates.

Check Recommendations

Follow the dynamic checklist for lowercase, uppercase, numbers, and symbols.

✓ 100% Client-Side Audit

Typed passwords never leave your browser, are never logged, and are never transmitted over network.

✓ Information Entropy (Bits)

Calculates true Shannon character-pool entropy log2(pool^length).

✓ Random Password Generator

Includes a built-in cryptographically secure random password generator.

🔒 Complete Client-Side Isolation

This tool runs entirely in your local browser runtime. No logs, analytics tracking, or remote server transmissions occur.

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