SECURITY BENCH
Calculate the Shannon entropy of a string from the frequency distribution of its characters. Useful for estimating the information density of a fixture, password, or token.
WHAT THIS DOES
Runs entirely in your browser.
/tools/entropy-calculatorentropy-calculatorv4.0.0LOCAL · LOCAL RUNIMPLEMENTED — This workbench is functional in the current release.Presets for this workbench
No preset yet. A preset stores the values in this form — never the result — and only for workbenches that run entirely in your browser.
Collections
Saved on this device only. Turn on sync to carry them to another device.
BATCH / ONE VALUE PER LINE
Up to 200 lines, one at a time, in this browser. Each line takes the place of text and everything else stays as you set it. Nothing is uploaded, and the row limit is not exceeded silently.
METHOD / LOCAL RUN
For each unique character, compute p = count / length. Shannon entropy H = -Σ p × log2(p).
Boundary: Per-character entropy only. Does not model multi-character context or attacker capability.
The calculation or transformation runs in your browser using the values entered above. No input is sent to UtilityForge for this tool.
EXAMPLES / LOCAL RUN FIXTURES
FAQ
No. UtilityForge is a local workbench. Use a real password manager and authentication system for credentials.
No. The entropy calculator runs locally; nothing is sent to UtilityForge.
The workbench states the exact method behind every result — the formula or procedure this page runs — so you can verify the computation instead of trusting a black box.
No. This workbench runs in the page: Text are read by the code your browser already downloaded, and UtilityForge receives neither the values nor the result.
Yes, and it is enforced rather than advertised: Text (100,000 characters). The limit is a browser input limit on a tool that runs on this device, so nothing is truncated after being sent anywhere.
Per-character entropy only. Does not model multi-character context or attacker capability.
RELATED TOOLS
LOCAL — Runs entirely in your browser.
COMMON USE CASES / SOURCE NOTE
Last reviewed:
Source information: Local Shannon entropy over character frequency distribution; text is not transmitted.