免费密码强度检查器
Enter any password to see how strong it is, how long it would take to crack, and how to make it better.
Character Checks
How Password Strength Is Calculated
Password strength depends on two main factors: length and character variety. We calculate entropy · the number of possible combinations an attacker must try. More character types (uppercase, lowercase, numbers, symbols) and longer passwords exponentially increase the difficulty of brute-force attacks.
What Does "Crack Time" Mean?
We estimate how long it would take an attacker making 10 billion guesses per second (a realistic rate for modern GPU clusters) to brute-force your password. This is a worst-case scenario · real attacks may be faster if you use common words or patterns. Always aim for "centuries" or higher.
Frequently Asked Questions
Is my password sent to a server?
No. All analysis happens in your browser. Your password never leaves your device.
How many characters should my password be?
At least 12 characters for most accounts, 16+ for important ones (banking, email, password managers). Longer is always better.
Is a passphrase better than a random password?
A passphrase (like "correct-horse-battery-staple") can be very strong if it's long enough (4+ random words). They're easier to remember but should be truly random · not song lyrics or quotes.