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Free Password Entropy
Calculator

Separate mathematical random-source entropy from real-world user-choice risk, find predictable patterns locally, model guess rates, and check modern password-policy guidance without uploading your password.

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FreeUse this tool without paying.No sign upStart with the tool right away.Clear stepsRead the tool’s own guidance.

About Free Password Entropy Calculator

Random-source ceiling: length × log₂(character pool) assumes each character was independently and uniformly selected. That is appropriate for CSPRNG-generated strings, not ordinary human choices.

Workspace options

  • Value to analyze
  • How was it created?
  • Primary guess rate
  • Guesses per second
  • Authentication context
  • Composition rules

Available actions

  • Analyze
  • Guess-time lab
  • Policy checker
  • Methodology
  • Reveal
  • Generate random