How To Calculate Gross Margin

Gross margin is gross profit divided by revenue. A business with two hundred and fifty thousand of revenue and one hundred and fifty thousand of cost of goods sold has forty percent, meaning forty cents of every revenue dollar survives the direct cost of producing what was sold.

Cost of goods sold is deliberately narrow. It covers materials, direct labour and manufacturing overhead that is tied to production. It excludes rent on the office, sales salaries, marketing and admin, all of which are operating expenses that come further down the income statement.

The distinction between gross margin and markup is the single most common confusion in this area. Markup divides gross profit by the cost of goods sold, gross margin divides it by revenue. The same numbers give forty percent and sixty six point seven percent respectively, and they are not interchangeable.

The relationship between them is fixed rather than arbitrary. Markup equals gross margin divided by one minus gross margin, so a fifty percent markup on cost corresponds to a thirty three point three percent margin on revenue. Knowing one always gives the other.

Gross margin is a statement about production efficiency and pricing power rather than profitability. A business can have an excellent gross margin and still lose money if its fixed operating costs are too large, which is exactly what happens to thin-margin businesses with heavy overheads.

Comparisons are only meaningful within an industry. Software businesses routinely report gross margins in the eighties or nineties, retailers in the twenties and thirties, and manufacturers somewhere in between depending on materials intensity. A low margin in one sector can be excellent in another.

The ratio is a useful screening tool for pricing decisions. If gross margin falls while revenue rises, the business is buying volume with price or is absorbing input cost increases, and either trend shows up in the ratio long before it shows up in net profit.

It is also the metric behind break-even analysis, because fixed operating costs are covered out of gross profit. The contribution margin generalises the same idea down to a single product, where variable cost is compared to price rather than total cost to total revenue.

A single period is noisy. Seasonal discounting, a one-off materials spike or a change in the product mix can all move gross margin sharply, so the trend across several periods usually says more than any one number.

Inventory accounting affects the cost of goods sold and therefore the margin. The method used should be consistent across periods, because switching methods changes the reported cost without any change in the underlying business.

Finally, gross margin is not cash. A sale that is invoiced but unpaid still counts as revenue, and the cash arrives later or not at all, so gross margin has to be read alongside the working capital position to mean much.