Password Strength Checker
Check how strong your password is — analysed entirely in your browser, never sent anywhere.
About this tool
This checker scores your password based on length, character variety, and estimated entropy, and
flags common weak patterns like password or 123456. All analysis happens
locally in your browser using JavaScript — your password is never transmitted or stored anywhere.
How the strength score works
The checker looks at several factors together, rather than any single rule:
- Length — longer passwords score higher, since they're exponentially harder to brute-force.
- Character variety — using a mix of uppercase, lowercase, numbers and symbols increases the possible combinations an attacker would need to try.
- Estimated entropy — a rough measure of unpredictability based on password length and the variety of unique characters used.
- Common patterns — well-known weak passwords and predictable sequences are flagged regardless of length.
Is it safe to type my real password in here?
Yes — the check runs entirely in your browser via JavaScript. Nothing is sent to a server, logged, or stored. You can also disconnect from the internet and the tool will still work.
My password scored "Fair" — what should I change?
Usually the fastest win is length: adding a handful of extra characters improves the score more than swapping letters for symbols. Try the Password Generator for a strong, ready-made alternative.
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