How Do You Calculate Profit? (gross, operating, and net)

Profit is revenue minus costs. The whole question is which costs you subtract — and there are three useful answers.

The three profit numbers

ProfitFormulaWhat it tells you
Gross profitRevenue − cost of goods soldWhether your pricing works
Operating profitGross profit − operating expensesWhether your business model works
Net profitOperating profit − interest − taxWhat you actually keep

A worked example

A small product business does $120,000 in sales over a year.

  • Cost of goods sold (materials, production labor, packaging, shipping): $54,000 → gross profit $66,000 (55% gross margin)
  • Operating expenses (rent $9,000, software $3,600, marketing $12,000, admin $18,000): $42,600 → operating profit $23,400
  • Interest $1,400 and tax $4,400 → net profit $17,600 (14.7% net margin)

Profit per sale vs profit per period

Profit per sale is price minus unit cost — useful for pricing decisions. Profit per period is revenue minus all costs for a month or year — useful for knowing whether the business is viable. A product can be profitable per sale and the business still lose money if volume doesn't cover fixed costs.

Three things that quietly destroy profit

  1. Unpaid owner labor. If your time isn't in cost of goods sold, gross profit is fiction.
  2. Fees. Marketplace and payment fees of 8–12% come straight out of gross profit.
  3. Discounts and returns. Your average selling price is almost always below list. Measure profit on the average, not the list price.

Turning profit into a percentage

Divide profit by revenue. $17,600 ÷ $120,000 = 14.7% net margin. Percentages let you compare periods and businesses of different sizes; dollars tell you what's in the bank.

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Last reviewed: 2026-09-18 · Back to all guides