About Index of Coincidence
Index of Coincidence (IC) is the probability of two randomly selected characters being the same. This can be used to determine whether text is readable or random, with English text having an IC of around 0.066. IC can therefore be a sound method to automate frequency analysis.
Input: text. Output: a numeric value.
Format reference: Index of Coincidence background and specification
Example
Use “Try example” to load this public sample and its settings, then run it.
Input
Hello world, this is a test to determine the correct IC value.
Result
The example demonstrates the configured operation. Generated values, timestamps or formatting may vary between runs.
Parameters
This tool does not need additional parameters.
Before interpreting the result
These tools have specialized conventions. Read the operation description and parameter choices before interpreting the result.
How to use this page
- Paste your input or open a local file.
- Adjust tool options if needed, then choose Run tool.
- Copy the result or download the original output bytes.
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