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Password Strength Checker

Check how strong your password is locally — entropy analysis, time-to-crack estimate, and zero data upload.

Hash Generator (Bcrypt/SHA)Password GeneratorSecret Scanner
Password Strength Checker
Analyzed locally — your password never leaves this page.
Real-time analysis Zero uploads
Enter Password Analyzed in real time
Enter a password
Analysis Breakdown Detailed metrics
Length0
Entropy0 bits
Uppercase✗
Lowercase✗
Numbers✗
Symbols✗
Ready Browser only
Type a password above to see its strength analysis.
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Password Strength Checker

Knowing whether a password is strong enough before using it can prevent costly security incidents. This password strength checker analyzes your password entirely in your browser — the password never leaves your device, making it safe to test even production credentials.

The tool evaluates multiple factors: character length, character diversity (uppercase, lowercase, numbers, symbols), entropy bits (a mathematical measure of randomness), and provides a realistic time-to-crack estimate based on 10 billion guesses per second — the approximate speed of modern GPU-based cracking hardware.

Results update in real time as you type, giving you immediate feedback without clicking any buttons. The strength scale ranges from Very Weak to Very Strong, with specific guidance on what makes each password vulnerable or resilient.

How to Use the Password Strength Checker

  1. Type or paste a password into the input field.
  2. Watch the strength meter and grade update in real time.
  3. Review the breakdown: length, entropy, character types, and time-to-crack.
  4. Adjust your password until you reach 'Strong' or 'Very Strong' rating.

Password Strength Checker Examples

Before 
password123
After 
Score: Weak | Entropy: 36 bits | Time to crack: 2 minutes

Frequently Asked Questions

  • Is my password sent to a server for analysis?

    No. All analysis runs locally in your browser using JavaScript. Your password never leaves your device.

  • How is time-to-crack calculated?

    We estimate based on 10 billion guesses per second, which represents modern GPU-based cracking speeds. The actual time depends on the attacker's hardware.

  • What entropy level is considered secure?

    A password with 80+ bits of entropy is considered very strong. Most 16+ character passwords with mixed character types exceed this threshold.

  • Does this check against known breached passwords?

    This tool focuses on mathematical strength analysis. For breach checking, consider using haveibeenpwned.com's API separately.

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Hash Generator (Bcrypt/SHA)Password GeneratorSecret Scanner