PPM = (Number of defective units / Total units) × 1,000,000
PPM = (Number of defects / Total opportunities) × 1,000,000
Convert the defect rate to a decimal
Multiply the decimal by 1,000,000
Example: 5 defects in 2,000,000 units = (5 / 2,000,000) × 1,000,000 = 2.5 PPM
Example: 12 defects in 3,000,000 opportunities = (12 / 3,000,000) × 1,000,000 = 4 PPM