DPMO Calculator
Enter the number of defects, units inspected, and opportunities for defect per unit to find the DPMO and yield.
How DPMO is calculated
DPMO (Defects Per Million Opportunities) is a Six Sigma quality metric calculated as DPMO = (defects / (units × opportunities per unit)) × 1,000,000. It normalizes defect counts to a consistent scale regardless of how many units or opportunities were actually inspected.
An "opportunity" is any place a defect could occur on a single unit — a product with 4 critical dimensions has 4 opportunities per unit, for example. This lets DPMO fairly compare quality across products of very different complexity.
Frequently asked questions
Why use DPMO instead of a simple defect rate?
A simple defect rate (defects per unit) doesn't account for how complex each unit is. DPMO normalizes by the number of opportunities per unit, so a complex product with more chances to fail isn't unfairly compared to a simple one on equal footing.
What's considered a good DPMO?
Six Sigma quality (the namesake standard) corresponds to about 3.4 DPMO — extremely low. Many processes operate at a "four sigma" level, around 6,210 DPMO, which is still considered solid quality in many industries.
How do I determine the number of opportunities per unit?
Count every independent characteristic or step on a unit where a defect could occur — each critical dimension, each solder joint, each required field on a form, and so on. This requires judgment and should be defined consistently across your measurements for valid comparisons.