Password Strength Checker
Instantly test your password's security. Get real-time feedback on complexity, guessability, and estimated time to crack using the industry-standard zxcvbn-ts algorithm.
Analyze Your Password
Privacy Warning: This analysis is performed 100% locally in your browser. Our servers never see, save, or log your password. We use entropy calculation algorithms to estimate security without needing to transmit any sensitive data.
Why check your Password Strength?
Weak passwords are the most common entry point for data breaches. Our free tool uses advanced pattern matching, dictionary analysis, and entropy calculations to help you understand how secure your password really is before you use it on important accounts.
Patterns to Avoid
- • Keyboard sequences (qwerty, 12345)
- • Personal info (birthdays, names)
- • Common words or simple substitutions (P@ssw0rd)
- • Repeated characters or short lengths
Best Practices
- • Use 12+ characters (length is key)
- • Mix uppercase, lowercase, numbers, and symbols
- • Use "Passphrases" (random strings of unrelated words)
- • Use a unique password for every single account
Frequently Asked Questions
Is it safe to type my password here?
Yes. Unlike many other checkers, this tool runs entirely on your device. The code that analyzes your password is in your browser, not on our server. If you disconnect your internet, the tool will still work — that's how you know it's safe.
What is 'Entropy' in password security?
Entropy measures the randomness of a password. Higher entropy means there are more possible combinations, making it mathematically harder for a computer to guess through brute force.
How does the 'Time to Crack' estimate work?
We use the zxcvbn-ts library which simulates how hackers actually guess passwords using common word dictionaries, date patterns, and high-speed hashing hardware. It provides a realistic estimate of how long a dedicated attack might take.