A site once forced me to create a password with uppercase, lowercase, digit, symbol, and no dictionary words, so I used ‘P@ssw0rd1!’, which passed every rule and would fall to an attacker in seconds. Complexity rules measure obedience, not security. Entropy measures the actual search space an attacker must grind through, which is the only number that matters.
Enter a password to see its entropy in bits plus an estimated brute-force cracking time. The scale to internalize: under 40 bits is weak, 60+ is solid, 80+ is overkill for most purposes. Length dominates everything, a four-word passphrase (‘correct horse battery staple’ style) beats an 8-character symbol soup while remaining typable and memorable.
Try it now: open the free tool, runs 100{e0bed9560a59d6d3feee569f5ae3dad3ee14a646b3fccc2d16becbf099999e03} in your browser.
The honest security stack: a password manager generating unique 20+ character random passwords per site matters more than any single password’s strength; two-factor authentication (app or hardware key, not SMS) matters more than the manager; and breach checking matters most of all, a 100-bit password that’s been leaked is worth zero. Check Have I Been Pwned before admiring your entropy score. Also: this meter runs in-browser, which is exactly how password tools should work, never type real passwords into server-side checkers.
Bottom line: long and unique beats complex and reused, manager plus 2FA, entropy as your yardstick.
Your turn: use the tool free here, no signup, nothing leaves your device.
How do you use Password Entropy Meter & Brute-Force Estimator?
Open the Password Entropy Meter & Brute-Force Estimator in your browser (Just how strong is that password?). Type or paste your input, adjust the options, and copy the result. Everything runs locally on your device with no account and nothing stored, so the three steps below take seconds even for confidential work.
- Paste the data or snippet you want to process.
- Run the tool and watch the output update.
- Copy the result for use in your own code.
Try Password Entropy Meter & Brute-Force Estimator free. It opens right in your browser.