Calculate total revenue (sales) for the period
Calculate total costs for the period
Compute profit: profit = revenue − costs
Choose the profit margin type:
Gross profit margin: (gross profit ÷ revenue) × 100
Operating profit margin: (operating profit ÷ revenue) × 100
Net profit margin: (net profit ÷ revenue) × 100
Use the selected profit figure (gross, operating, or net) and divide by revenue
Multiply by 100 to express as a percentage
If using decimals instead of percentages: profit margin = profit ÷ revenue