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THE FEUTEX TOOLKIT

Process Capability Indices

Compare a stable process with specification limits using Cp, Cpk and one-sided capability indices.

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02 Your result
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FormulaCp = (usl-lsl)/(6*sd); Cpk = min(usl-mean,mean-lsl)/(3*sd); Cpu = (usl-mean)/(3*sd); Cpl = (mean-lsl)/(3*sd)
Sources and model references

How to use this tool

  1. Enter the labeled inputs using consistent units.
  2. Check the stated assumptions and calculate.
  3. Review each output and compare another input scenario.

Try this example

{
  "lsl": 0,
  "usl": 12,
  "mean": 7,
  "sd": 1
}

Accuracy and scope

Capability interpretation requires a stable process and appropriate distribution assumptions; negative Cpk is possible. Finite floating-point arithmetic; results can lose precision near singular or extreme inputs.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.