# Process capability

Process capability is a measurable property of a process against the specification, expressed as a process capability index (e.g., Cpk or Cpm). The output of this measurement is usually illustrated by a chronological control sample, a histogram and calculations that predict how many parts will be produced out of specification (OOS).

## How to calculate cpk in excel

Three possibilitis:

1. Excel template with Macro
2. Excel add in with office 365
3. online calculation

## 1. Excel template with Macros

One way is to use the excel template with macros. You will get an excel template with:

• multilingual (german, englisch, italian, other languages possible)
• normal distribution (two sided tolerance. one sided tolerance, …..)
• folded normal distribution (one sided technical tolerance – roughness, concentricity, etc…)
• histogram, probabiltiy plot, chronological plot
• possibiltiy to format the cells, integrate the logo of your company, etc…………….

and get your account data for the 14 day trial by using the above email box

## 2. Excel Add in with office 365

The base of the calculation is this spreadsheet without macros.

You can make all adjustments like:

• formatting cells
• etc., etc.

To calculate adjusted values, you need the Microsoft certified „Sixsigmablackbelt Analysis“ Excel „add in“.

The easiest way to get the „add in“ is to install the „add in“ via Excel.

If you do not have a template yet, press the button „Create template“. If you have opened the template above, simply change the values and press the „Calculate“ button.

### 28 seconds to get a process capability calculation

• just open it
• put the values in
• calculate the sheet
• and save the results

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## 3. Cpk online calculator

For a first overview you can calculate the Cmk online on this site. Just edit the values or delete the values and copy your own values from Excel via CTRL+V.

## Formula to calculate

The base for the cpk formula is described here.