Password Strength Checker
Real-time analysis of any password - entropy score, crack time estimation, character composition breakdown, and actionable improvement tips. Runs 100% locally in your browser.
Password strength is determined by entropy - a measure of unpredictability. The formula is: entropy = log2(charset^length). Using 94 ASCII characters at 16 characters long yields 100+ bits of entropy - practically unbreakable by brute force.
The crack time estimate assumes a GPU cluster at 10 billion guesses per second. A properly generated 16-character password would take longer than the age of the universe to crack.
Our checker screens against commonly used passwords, detects repeated patterns, and evaluates character diversity. The 0-100 score combines all factors into a single easy-to-understand rating.