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Password Strength Checker

Review a password locally for length, character variety and an approximate entropy score. The page gives an offline guessing estimate and specific improvement suggestions; it never sends the value anywhere. For maximum safety, test a memorable pattern rather than a live password.

🔒 100% private — files never leave your browser

Do not paste a production password into any online tool.

Strength scoreType a password to see a local estimate.

Estimated entropy

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Offline estimate

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Feedback

    How to use the Password Strength Checker

    1. 1 Type a sample password or phrase — do not paste a production credential.
    2. 2 Review the local strength level, entropy estimate and offline time estimate.
    3. 3 Use the feedback to lengthen and diversify the password, then create a unique credential with a password manager.

    Frequently asked questions

    Is the password sent to a server?

    No. The check runs entirely in your browser. Even so, do not enter a password that protects a real account into any online checker.

    What does entropy mean here?

    Entropy is a rough estimate based on length and the character groups present. Real attackers use dictionaries, leaked-password lists and patterns, so the displayed crack time is not a guarantee.

    Does a strong score guarantee a secure password?

    No. Use a long, unique password or passphrase generated and stored by a reputable password manager, enable multi-factor authentication and never reuse credentials.

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