Password Policy Strength Sim

Test what a password policy actually requires

A password policy is meant to force strong passwords, but many policies are stricter on paper than in effect. This simulator analyses password policy text for the entropy it actually guarantees and its compliance with good practice, so you can see whether a policy delivers the security it claims.

Why strict rules can be weak

Complexity rules, requiring a capital, a digit, a symbol, feel strong but often produce predictable passwords like Password1! that meet every rule and are trivially guessed. What actually matters is entropy, the unpredictability of the result, and length contributes far more to it than forced complexity. A policy that mandates fussy composition but permits short passwords can guarantee less entropy than one that simply requires length. Analysing the policy reveals that gap, which is invisible if you only read the rules.

Policy that actually protects

The tool runs entirely in your browser, so nothing you paste is uploaded, which is exactly what you want when the input is your own security-sensitive data.

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