How to Calculate Process Sigma - Formula, Example

Definition:

This tutorial explains how to calculate the process sigma value.

Example :

In hardware company hard disk manufactured is 10000 and the defects is 5. Find the process sigma.

Given :

Opportunities = 10000
Defects = 5

To Find :

Process sigma

Solution :

Substitute the given values in the formula, DPMO = (Total defect / Total Opportunities) x 1000000
= (10000/5) x 1000000
Defect (%) = (Total defect / Total Opportunities) x 100% = (10000/5) x 100
Yield (%) = 100 - Defect (%) = 100 - 0.05
Process sigma = 0.8406 + √(29.37)-2.221*(log(DPMO))
= 0.8406+sqrt(29.37)-2.221*(log(500))
= 4.79

Result :

Process sigma = 4.79