Password strength calculator

Enter your values

Estimate entropy and rough cracking windows locally in your browser. This page keeps password history disabled.

Runs in your browser. This calculator does not keep password history on the page.

All required fields must be filled in.

Estimated Strength

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Enter a password or passphrase to estimate rough entropy, pattern penalties, and online vs offline crack-time windows.

Example calculations

Tap an example to prefill the calculator with sample values.

Common seasonal pattern

Short mixed password with a predictable word and year

A password can use uppercase, digits, and a symbol but still be easy to guess if it follows a common pattern.

Result: Usually lands in the fair range, not strong.

Long passphrase

Multi-word phrase with digits and punctuation

Longer passphrases often outperform short random-looking passwords because length compounds the search space quickly.

Result: Typically produces a strong or very strong estimate.

Mixed random string

Longer mixed-character password without an obvious pattern

A high-entropy password can be strong without being a full passphrase if it avoids predictable themes and reuse.

Result: Usually produces a strong estimate with much better offline resistance.

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