Profit Margin Calculator

How to use the profit margin calculator

1. Enter revenue for the period: net sales after returns, refunds and discounts.
2. Enter cost of goods sold: what it cost to make or buy the things you sold in that period, including direct materials and direct labor.
3. Enter operating expenses: the costs of running the business that aren’t tied to each unit, such as rent, utilities, wages for staff outside production, marketing and software.
4. Enter interest, taxes and other items to get from operating income to net income. Use a negative number for a one-off gain.

The calculator opens on the income statement of Clear Lake Sporting Goods, the example company in the open textbook Principles of Finance 2e from OpenStax, so you can check the method before entering your own figures.

Gross, operating and net margin

Clear Lake had net sales of $120,000 and cost of goods sold of $60,000 in the current year, leaving gross profit of $60,000: a 50% gross margin. Its operating expenses were rent of $5,500, utilities of $2,500, depreciation of $3,600 and salaries of $5,400, which total $17,000. Operating income was $43,000, a 35.8% operating margin. After $5,000 of interest and $3,000 of income tax, net income was $35,000. OpenStax computes the profit margin as $35,000 ÷ $120,000 = 0.29, or 29%, which the calculator shows as 29.17% before rounding.

Each margin answers a different question. Gross margin shows whether the product itself is profitable. Operating margin shows whether the business as a whole is, before financing and tax. Net margin is the bottom line: how many cents of every sales dollar the owners keep.

What goes in each line

Cost of goods sold depends on the business. For a retailer, it is the cost of the merchandise sold. For a manufacturer, it is materials, direct labor and the factory overhead assigned to the products. For a service business, OpenStax notes it is mainly the labor and materials used to deliver the service.

Operating expenses are the indirect costs of being open: rent, utilities, office and sales salaries, insurance, advertising, software and depreciation on equipment.

Below the operating line come interest on loans, income tax and unusual gains or losses, such as selling an old vehicle for more or less than its book value.

Classification changes the gross margin, not the net margin. Moving delivery costs from operating expenses into cost of goods sold lowers gross margin and raises operating expense share, but the bottom line is the same. Pick a treatment and keep it consistent from period to period.

Margin is not markup

Margin divides profit by the selling price; markup divides it by the cost. An item that costs $60 and sells for $100 has a $40 profit, which is a 40% margin and a 66.7% markup. Confusing the two is a common way to underprice: adding a 40% markup to a $60 cost gives $84, which is only a 28.6% margin.

Use this page to measure the margins your whole business earned over a period. To set a price for one product from its cost and a target margin, use the markup calculator.

Seeing what moves your margins

Because margins are shares of revenue, small changes in price or cost have outsized effects on net margin. Starting from Clear Lake’s figures:

• Raise prices 5% with the same costs and volume: revenue becomes $126,000, net income $41,000, and net margin rises from 29.2% to 32.5%.
• Cut cost of goods sold 5% by negotiating with suppliers: $57,000 instead of $60,000 lifts net income to $38,000, a 31.7% net margin.
• Add $6,000 of advertising without extra sales: net income falls to $29,000, a 24.2% margin.

Type the changed figures in to test your own scenarios. Real price changes usually affect how much you sell, so treat these as a starting point rather than a forecast. The break-even calculator models how volume and costs interact.

Common mistakes

• Leaving out the owner’s pay. In a small business the owner’s work is a real cost. If you don’t pay yourself a wage, the margins overstate what the business earns on its own.
• Mixing periods. Revenue for a quarter against costs for a month gives a meaningless margin. Use the same dates for every line.
• Using cash in and out instead of earned and incurred. A big inventory purchase paid this month but sold over the next six will make this month look terrible and the next ones look great. Cost of goods sold counts only what was sold.
• Comparing with other businesses too literally. Margins vary widely by industry and business model. Your own trend over time is often the most useful comparison.

Gross margin for a single product

The same formula works per item. A product that sells for $40 and costs $22 to buy or make has a gross profit of $18 and a gross margin of 18 ÷ 40 = 45%. Enter the price as revenue and the unit cost as cost of goods sold, with zero for the other lines. Comparing products this way shows which ones carry the business and which ones only add volume.

Gross margin versus contribution margin

Gross margin subtracts cost of goods sold, an accounting category. Contribution margin, used in break-even analysis, subtracts every cost that varies with sales, which can include shipping, payment fees and sales commissions that sit in operating expenses on an income statement. For an online store, contribution margin is often well below gross margin. Use gross margin to compare with financial statements and contribution margin to decide whether one more sale is worth making.

Working back from a profit goal

To find the revenue a profit goal requires, separate the costs that scale with sales from those that don’t. If cost of goods sold runs at 50% of revenue, and operating expenses, interest and taxes come to about $25,000 a year regardless, earning $50,000 of net income needs (50,000 + 25,000) ÷ (1 − 0.50) = $150,000 of revenue. Enter $150,000, $75,000, $17,000 and $8,000 to confirm the result: a 33.3% net margin. In practice, income tax rises with profit, so treat the tax figure as an estimate.

Sources & assumptions

How this calculator gets its numbers. Full method: our methodology.

• Gross profit = revenue − cost of goods sold; operating income = gross profit − operating expenses; net income = operating income − interest, taxes and other items.
• Each margin is that profit ÷ revenue × 100; revenue of 0 leaves margins undefined.
• All figures should cover the same period and use the same accounting basis.

Sources

1. OpenStax (Rice University), Principles of Finance 2e, 5.1 The Income Statement. Net sales − cost of goods sold = gross profit; gross profit − operating expenses = operating income; Clear Lake Sporting Goods: $120,000 net sales, $60,000 COGS, $17,000 of operating expenses, $43,000 operating income.
2. OpenStax (Rice University), Principles of Finance 2e, 6.6 Profitability Ratios and the DuPont Method. Profit margin = net income ÷ net sales; Clear Lake’s $35,000 ÷ $120,000 = 0.29, or 29%.

Last reviewed November 2, 2026. How costs are classified changes gross margin but not net margin; keep the treatment consistent between periods.