Profit margin is one of the most important numbers in any business — it tells you how much of every pound, dollar, or rand you collect actually becomes profit after covering costs. Yet many business owners confuse margin with markup, misquote their profitability to clients or investors, or simply price products without understanding whether they are making money on them at all.
This guide covers the margin vs markup distinction (they are not the same thing), what a good profit margin looks like across different industries, and how to calculate margin, selling price, and cost price instantly using a free calculator.
Profit margin expresses profit as a percentage of revenue (selling price). It answers the question: "For every £1 I collect, how much is profit after I have covered my costs?"
Formula: Profit Margin % = (Selling Price − Cost) ÷ Selling Price × 100
Example: You sell a product for £150 that cost you £100 to produce or buy. Your profit is £50. Your profit margin is (£50 ÷ £150) × 100 = 33.3%. You keep 33 pence of every pound you collect.
Profit margin is a revenue-based metric. It tells you how efficiently you convert revenue into profit. Investors, accountants, and analysts use margin as the standard profitability measure because it expresses profit relative to what you actually earn, not what you spend.
Markup expresses profit as a percentage of cost. It answers: "How much more than my cost am I charging?"
Formula: Markup % = (Selling Price − Cost) ÷ Cost × 100
Same example: Cost £100, Selling Price £150. Markup = (£50 ÷ £100) × 100 = 50%. You charged 50% more than your cost.
Margin and markup describe the same transaction but produce different numbers. This causes genuine confusion when suppliers, buyers, or colleagues quote figures without specifying which they mean:
These look similar but they produce different prices. A retailer who confuses "50% margin" with "50% markup" will significantly underprice their products. Markup always produces a higher percentage figure than margin for the same transaction — the same profit looks bigger expressed as markup.
Rule of thumb: Retailers typically quote markup when setting prices. Accountants and investors quote margin when analysing profitability. Know which one your counterpart is using before agreeing to anything.
The free profit margin calculator handles all three calculation directions:
You know what you paid (or it costs you to produce) and what you charge. Enter cost and selling price and the calculator shows your profit margin, gross profit, and markup percentage instantly.
Use this to audit your existing prices. Are you hitting your margin targets? Are different product lines performing differently?
You know your cost and you have a target margin in mind. Enter both and the calculator tells you what selling price you need to achieve that margin.
Formula used: Selling Price = Cost ÷ (1 − Target Margin %)
Example: Cost £80, target margin 40%. Selling Price = £80 ÷ (1 − 0.40) = £80 ÷ 0.60 = £133.33.
This is the correct way to price products to a margin target — not multiplying cost by (1 + margin), which gives you a markup calculation, not a margin calculation.
You know what the market will pay and you have a margin target. The calculator tells you the maximum cost you can afford while still hitting your margin.
Formula used: Cost = Selling Price × (1 − Target Margin %)
Example: Market selling price £200, minimum margin target 35%. Maximum cost = £200 × (1 − 0.35) = £200 × 0.65 = £130. If your cost exceeds £130, you cannot meet your margin target at this price.
This direction is particularly useful for procurement decisions, manufacturing costing, and negotiating with suppliers.
Margin expectations vary enormously by industry. A 5% margin is excellent in grocery retail and dangerous in consulting. Here are realistic benchmarks:
A margin below 10% leaves very little buffer for unexpected costs, price competition, or a slow quarter. Most business advisors suggest aiming for at least 20% gross margin to have a sustainable business with room to absorb volatility.
Gross margin measures profitability after subtracting the direct cost of producing or acquiring goods (Cost of Goods Sold — COGS). It does not include overhead, salaries, rent, or marketing. Gross margin tells you whether your pricing is fundamentally sound.
Net margin measures profitability after all expenses — including overhead, taxes, interest, and depreciation. This is the "bottom line" number. A business with a healthy gross margin can still have a poor net margin if overhead is too high.
For pricing decisions, track gross margin. For overall business health and investment decisions, track net margin. Most small business owners should focus on gross margin first — it is the lever they have most direct control over through pricing.
Why does a 50% markup not equal a 50% margin?
Because they use different denominators. Markup divides profit by cost; margin divides profit by selling price. The selling price is always larger than cost (assuming a profitable transaction), so dividing by selling price gives a smaller percentage. A 50% markup always produces a 33% margin, not 50%.
Can profit margin be negative?
Yes — a negative margin means you are selling below cost. This happens during launch promotions, clearance sales, or loss-leader pricing. Sustainable businesses cannot maintain negative margins for long. Our calculator shows negative margin in red as an immediate flag.
Should I include VAT in my margin calculation?
No. VAT is collected on behalf of the government and is not your revenue. Always calculate margin on net (ex-VAT) selling price and net (ex-VAT) cost. Including VAT inflates your apparent revenue without actually changing your profitability.
What is the difference between gross profit and gross margin?
Gross profit is a currency amount (e.g. £500). Gross margin is a percentage (e.g. 33%). Both describe the same thing — the profit after direct costs — just expressed differently. Use amounts for absolute tracking, percentages for comparison across different products or periods.
Use our free Profit Margin Calculator tool — works in your browser, nothing to install.
Profit Margin Calculator — Free