Password Strength Checker
Check the strength of a password using entropy analysis and common patterns.
Strength
Very Weak
Entropy
0 bits
Checklist
Estimated brute-force time
Frequently Asked Questions
Why did a long password still get downgraded?
Length helps, but the checker also penalizes repeated characters, sequential runs like `abc` or `123`, and built-in keyboard/common patterns like `qwerty`, `password`, `admin`, and `letmein`. A long but predictable password can still score lower.
Does this compare my password against leaked password databases?
No. Everything here is local and heuristic-based; it does not call Have I Been Pwned or any other breach list.
What counts as a 'common pattern' in this checker?
It looks for triple repeats like `aaa`, forward or reverse alphabet and digit sequences, and a short hardcoded list of keyboard-style words. It is a useful heuristic, but not a full password-auditing engine.
What do the brute-force times actually mean?
They are rough estimates derived from the calculated entropy at 1K, 1M, 1B, and 1T guesses per second. They are illustrative numbers, not a promise of real-world cracking time.
How is the entropy score calculated here?
The tool estimates charset size from the character types you used, then multiplies password length by `log2(charset size)`. That is why adding uppercase, digits, or symbols can move the bits number quickly.