Does this tool send my password anywhere?

No. All calculations run in JavaScript in your browser. You can verify this by opening DevTools and watching the network tab — no request is made when you type.

What entropy counts as strong?

Under 28 bits is weak, 28–50 is fair, 50–80 is good, and 80 or more is strong against offline attacks on modern hardware.

Are passphrases safer than complex passwords?

Usually yes. Four random words from a 7,776-word list give about 51 bits of entropy and are far easier to remember than a random 10-character string.

Password Security Checker

Analyze your password's strength with entropy calculation, crack time estimates for multiple attack scenarios, and common password detection.

Strength: awaiting input0 bits of entropy

Type a password above to see entropy, crack time, and common-password check.

Password Details

Length

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Charset Size

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Entropy

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Estimated Crack Time

Online attack (throttled)

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Offline attack (fast hash, e.g. MD5)

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Nation-state (specialized hardware)

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Passphrase Suggestion

Passphrases — multiple random words joined together — are easier to remember and harder to crack than short complex passwords.

anchor-barrel-candle-donkey

Entropy: 28.48 bits — equivalent to a 5-character random alphanumeric password

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