Gross Margin Calculator — Profit, Margin, Markup

Margin tells you what you keep, not whether you survive

An 80% gross margin looks excellent until you see what it costs to acquire each customer. A 20% margin looks precarious until you notice the volume — 20% of $100M is $20M, which is serious money. Gross margin measures what each unit of revenue leaves behind after the direct cost of delivering it, and that remainder is the entire pool available to fund salaries, rent, marketing, product development and everything else. A healthy gross margin is necessary for profitability but nowhere near sufficient.

The formula

Gross margin is (revenue − COGS) ÷ revenue, expressed as a percentage.

Take $100,000 of revenue against $60,000 of cost of goods sold. Gross profit is $40,000, and the margin is $40,000 ÷ $100,000 = 40%. In plain terms, 40 cents of every revenue dollar survives the direct cost of delivery. That $40,000 — not the $60,000, which is already spent on the goods themselves — is what has to cover every other cost in the business. If operating expenses come to more than $40,000, the business loses money despite a perfectly respectable margin.

Why the ratio shapes the business model

This is the number that constrains what kind of company you can be. A business at 20% gross margin has to run its entire operation on 20 cents in the dollar, which forces high volume, tight overheads and little room for a large sales team. One at 80% can afford substantial spending on acquisition, support and R&D from the same revenue.

Two companies with identical revenue and identical net profit can therefore be in completely different shape. The one with the higher gross margin has more levers to pull and more room to absorb a bad quarter.

Three things this number deliberately omits

Operating expenses are invisible. Gross margin excludes salaries, rent, software and advertising entirely. A company with an 85% gross margin fails just as reliably as any other if its operating costs consume more than 85% of revenue — and companies with excellent gross margins go under regularly for exactly that reason.

The COGS boundary is genuinely ambiguous. What belongs in cost of goods sold varies between businesses, and the choices are defensible either way. One software company counts hosting as COGS; another files it under operating expenses. Payment processing fees, support staff, shipping and returns all get classified differently. This makes cross-company margin comparison unreliable unless you know what each side included.

It is a ratio, not an amount. A 90% margin on $1,000 of annual revenue is $900 of gross profit, which pays nobody. A 15% margin on $10M is $1.5M. Watch for the pattern where margin percentage rises while gross profit in currency falls — that combination is common and it is not good news. Track both.

Markup is the same profit expressed differently

The tool shows the equivalent markup alongside the margin. A 40% gross margin is a 66.67% markup, because markup divides the same profit by cost rather than by revenue — a smaller denominator, so always a larger percentage. For pricing from a cost target and converting between the two, see the Markup Calculator.

What moves margin in practice

Rising input costs cut margin directly. Product mix shifts it without any individual product changing — if high-margin lines sell less and low-margin lines sell more, blended margin falls on its own.

Discounting deserves particular attention, because the effect is larger than it looks and there is a simple rule for it: the share of unit profit a discount consumes is the discount divided by the margin. A 5% discount on a 20% margin product costs 5 ÷ 20 = a quarter of the profit on that unit. The same 5% on a 60% margin product costs only a twelfth. This is why routine discounting is survivable for high-margin businesses and quietly fatal for thin-margin ones.

To model whether your gross profit actually covers fixed costs, the Break-Even Calculator is the next step. This is general business information, not financial advice.