Process Capability (Cp / Cpk)

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1. Load measurement data
Instructions
  1. Load your measurements: Upload Excel (one measurement per row) or Paste values (one per line, optionally value,subgroup). You can download the Excel template with instructions and example data.
  2. In the configuration panel choose the Value column and how subgroups are defined: fixed size n (use 1 for individual measurements) or by ID column.
  3. Enter at least one specification limit (LSL and/or USL). Target is optional and only enables the Taguchi index Cpm.
  4. Optionally choose the within-subgroup estimate and whether to use unbiasing constants (c4 / d2), then click Analyze.
  5. Read the report: charts with their statistics on the right, and plain-language advice at the bottom of the page.
  • Measurements must be numeric: use a dot as the decimal separator, without units (10.02, not 10.02 mm).
  • At least 3 measurements are required; 25-30 or more are recommended for a reliable result. At least 2 subgroups are needed for the Pooled / Rbar / Sbar estimates.
  • Registered users can export the full report to PDF.
One measurement per row. If the workbook has several sheets, you choose the data sheet in the next step.