Six Sigma Calculator

Use this Six Sigma Calculator to calculate the DPMO, DPO, DPU, Sigma Level and the process Yield, based on the number of units, number of defect opportunities per unit, and the number of defects.

What Is Six Sigma?  Six Sigma (6σ) is an established framework that employs a data-driven approach to reduce defects, ensure quality control, enhance management, eliminate waste, improve service delivery, and manage other operational activities.

Calculator Definitions

Defects per Unit (DPU): The total defects within a sample divided by the number of units that were sampled. For instance, if we sampled 800 units and detected 50 defects, the DPU would be as follows:

50 / 800 = 0.0625.

Defects per Opportunity (DPO): The total defects within a sample divided by the total defect chances. For instance, if we sampled 800 units and found 50 defects with 5 opportunities per unit, the DPO would be as follows:

50 / (800 × 5) = 0.0125.

Defects Per Million Opportunities (DPMO): The total defects in a sample divided by the total defect chances multiplied by 1 million. For instance, if we sampled 800 units and found 50 defects with 5 opportunities per unit and multiplied this figure by 1 million, the DPMO would be as follows:

50 / (800 × 5) × 1000000 = 12500.

Yield: The percentage of a process that is free of defects. To calculate process yield, we use the following formula:

Yield (%) = (1 − DPO) × 100

Sigma Level: Organizations determine the sigma levels of given processes (one sigma, six sigma, etc.) as a means of comparing the performance of those processes throughout the entire organization as distinct elements. Sigma process levels 1-6 have a theoretical defect rate that is set as follows:

1 Sigma = 691,462 DPMO, 30.85% defect-free

2 Sigma = 308,538 DPMO, 69.146% defect-free

3 Sigma = 66,807 DPMO, 93.319% defect-free

4 Sigma = 6,210 DPMO, 99.379% defect-free

5 Sigma = 233 DPMO, 99.977% defect-free

6 Sigma = 3.4 DPMO, 99.99966% defect-free.