Password generator · Guide

Password Length and Entropy

Entropy is the precise way to talk about password strength. Understanding it explains why length wins.

Entropy in plain terms

Entropy measures unpredictability in bits — roughly, how many guesses an attacker needs. Each added random character multiplies the possibilities, so length raises entropy fast.

Length beats tricks

Substituting @ for a in a dictionary word adds little entropy because attackers know the trick. A longer truly random string adds far more, which is why generators favour length.

Frequently asked questions

Can I use this for production work?

Yes, for inspection, formatting and quick generation. Still review the output before committing it to production code or configuration.

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