# Cpk Calculator

Cpk Calculator calculates the minimum value of the process capability index. Process capability index(Cpk) is an important statistical tool. Process capability refers to the arithmetical study of the natural process variability of the given responsibilities in consideration.

## What is Cpk Calculator?

Cpk Calculator is an online tool that helps to calculate the minimum value of the process capability index. This online cpk calculator helps you to calculate the minimum value of the process capability index in a few seconds. To use this cpk calculator, enter the values in the given input box.

## How to Use Cpk Calculator?

Please follow the steps below to find the minimum value of the process capability index using an online cpk calculator:

**Step 1:**Go to Cuemath’s online cpk calculator.**Step 2:**Enter the values in the given input box of the cpk calculator.**Step 3:**Click on the**"Calculate"**button to find the minimum value of the process capability index.**Step 4:**Click on the**"Reset"**button to clear the fields and enter new values.

## How Cpk Calculator Works?

**Cpk **formula helps in calculating the process capability index (cpk), which is the measure of process capability. This value depicts how closely a process is able to produce the output to its overall specifications. The formula to calculate the process capability index is given by

Cpk = min[(USL−mean)/3σ, (mean−LSL)/3σ]

Where USL is the upper specification limit, LSL is the lower specification limit, and σ is a standard deviation

Let us understand this with the help of the following example.

**Solved Example on cpk**

Find the minimum value of process capability index (cpk) if USL is 50 units, LSL is 40 units, the standard deviation is 2 units, and the mean is 41 units and verify it using the cpk calculator?

**Solution**:

Given: USL = 50 units, LSL = 40 units, standard deviation = 2 units, and mean = 41 units

Cpk = min[(USL - mean)/3σ, (mean - LSL)/3σ]

= min[(50 - 41)/6, (41 - 40)/6]

= min[11/6, 1/6]

Therefore, the minimum value of process capability index (cpk) is 1/6

Now, try the cpk calculator and find the minimum value for:

- USL = 28 units, LSL = 19 units, standard deviation = 2 units, and mean = 22 units
- USL = 45 units, LSL = 25 units, standard deviation = 4 units, and mean = 19 units