Password Strength Checker

Analyze your password strength, entropy, and crack time. Everything runs in your browser.

Your password is never stored, transmitted, or logged. All analysis happens entirely client-side in your browser.

Enter Password

Enter a password above to analyze its strength

We will check entropy, crack time, and common patterns

How Does the Password Strength Checker Work?

This tool analyzes your password using multiple techniques to give you an accurate picture of how secure it really is. It calculates Shannon entropy based on the character set used, estimates crack time against various attack speeds (from online throttled attacks to fast offline GPU cracking), and checks for common weaknesses like dictionary words, keyboard patterns, and repeated characters.

What makes a strong password?

A strong password is long, unpredictable, and avoids common patterns. Mixing uppercase and lowercase letters, numbers, and special characters increases the character pool, but length matters most. A 20-character passphrase of random words is typically stronger than a short string of mixed symbols. Avoid names, dates, dictionary words, and common substitutions like "p@ssw0rd" which are easily detected by modern cracking tools.

Is it safe to type my password here?

Yes. This password checker runs entirely in your browser using JavaScript. Your password is never sent to any server, stored in any database, or logged in any way. All analysis (entropy calculation, pattern detection, dictionary matching, and crack time estimation) happens locally on your device. You can verify this by using the tool with your network disconnected.