Entropy Calculator
Estimate string entropy and password strength.
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Shannon entropy (bits/char)
0.000
Strength (estimate)
Weak
Length
0
Scores are heuristics for education only — not a guarantee of security.
How to use
- Enter a password or string.
- Review Shannon entropy and strength estimate.
Sample
Tr0ub4dor&3FAQ
What is Shannon entropy here?
It measures character distribution in the string, not resistance to all attacks.