Test your password strength instantly. Get entropy score, crack time estimate, and actionable tips to create stronger passwords. 100% client-side, your password never leaves your browser.
This tool analyzes your password using industry-standard entropy calculations and pattern detection. All analysis happens locally in your browser — your password is never sent to any server. Use this to audit existing passwords and learn what makes a password truly strong.
Yes. All analysis happens entirely within your browser using JavaScript. Your password is never transmitted over the network or stored anywhere. However, for maximum peace of mind, you can enter a password with a similar structure instead of your exact password.
Entropy measures the randomness of a password in bits. Higher entropy means more possible combinations, making the password harder to guess. Each additional bit doubles the number of possible combinations.
Crack time is a theoretical estimate assuming an attacker can try 10 billion passwords per second (roughly the speed of a modern GPU cluster). In reality, online attacks are much slower due to rate limiting, but offline attacks on leaked databases can approach this speed.
A strong password is: (1) long (12+ characters), (2) complex (mix of character types), (3) unique (not reused across sites), (4) random (not based on dictionary words or personal info), and (5) not in any known breach database.