Those Boring Tools
Security ToolsPrivate by design

Entropy to Password Length Calculator

Enter a target entropy in bits and a character set to calculate the password length needed to reach it.

How to use this tool

  1. 1Enter your target entropy in bits.
  2. 2Choose a character set.
  3. 3See the required password length.

Frequently asked questions

How is this different from the password entropy calculator?+

That tool measures the entropy of a password you already have; this one works backwards, telling you how long a password needs to be to hit a target entropy.

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