Cp Cpk Template for Excel
You Don't Have to be a Statistician to Calculate Cp and Cpk
Just Drop Your Data Into QI Macros Fill in the Blank Template
Input your target value, tolerances and measurements in the yellow shaded areas. The worksheet will automatically calculate Cp, Cpk, Pp, and Ppk. It has space for up to 35 characteristics and 100 measurements:
Here is an Example of the QI Macros Cp Cpk Template
There are Five Worksheets in the Template
- Cp Cpk 8 Worksheet - for up to 8 Characteristics with 100 measurements each
- Cp Cpk 35 Worksheet - for up to 35 Characteristics with 100 measurements each
- Attribute Cp Cpk Worksheet for Go/NoGo data - for pass/fail (binary) data where there are no measurements.
- Cp Cpk True Position - when there are two aspects to your measurement (e.g. horizontal and vertical for the position of a hole.)
- MMC Cpk True Position - when you are measuring something like the inside and outside of a cylinder
Compatible with One Sided Spec Limits
If you need to perform a one tailed capability analysis, just delete the formula in either the USL or LSL field.
To open the Cp Cpk template from the QI Macros menu, select Capability Templates, then Cp Cpk Templates.
To expand the template, follow these instructions.
Don't Try This at Home
You can try to calculate Cp, Cpk and Pp Ppk manually, but you'll probably make mistakes and aggravate customers. And you will find your homegrown template hard to maintain. Or you could use proven software like QI Macros for Excel. Based on calls to our tech support line, most people who try to perform manual calculations or build their own Excel formulas end up with incorrect results. Then they question our results!
For example, they use standard deviation instead of sigma estimator for Cp and Cpk. Or they get the constant wrong based on their sample size. Or they don't understand there are several methods of calculating sigma estimator.
If you're providing these results to your customers shouldn't you use a tool that's proven and affordable?
Learn More ...
- Process Capability Analysis Quick Reference Card (PDF, 172 KB)