How this instrument works
Profit is a single dollar figure — selling price minus cost — but it can be measured against either side of that subtraction, and the two readings rarely match. A $60 item priced at $100 clears $40 of profit; stack that $40 up next to the $100 price and it reads as a 40% margin, but stack the same $40 up next to the $60 cost instead and it reads as a 66.7% markup — one number, two denominators, two very different-looking percentages.
This sheet works at the level of a single item rather than a company's whole income statement — the price a buyer sets before a product goes on the shelf, in a catalog, or into a quote. Retailers often reach for a shortcut called keystone pricing: double the cost to set the price, which is a 100% markup but only a 50% margin. Typing a target percentage into the wrong field is a common pricing slip in retail and e-commerce, and it quietly gives away real profit rather than announcing itself as an error.
The instrument only knows the cost and price entered for one item; it leaves out payment-processing fees, shipping, returns, marketing and every other cost of actually making the sale, so the margin and markup shown here are gross figures for that single item, not a blended figure for a whole catalog or a company's reported income statement.
- Enter Cost, $ — what the item costs to buy in or produce, before any markup or margin is applied.
- Enter Selling price, $ — the price charged, or being considered, for that same item.
- Read Profit for the dollar amount left over once cost is subtracted from price.
- Compare Margin, % of price against Markup, % of cost — same profit, two different denominators.
- Change either figure and watch the two percentages move at different rates — markup always sits above margin once profit is positive.
Worked example — the $60 item sold at $100
Buy an item for $60 and sell it for $100. Profit is $100 minus $60, or $40. Measured against the $100 selling price, that $40 is a 40% margin. Measured against the $60 cost, the identical $40 is a 66.6666666667% markup, which the sheet rounds to 66.67% for display. Same sale, same $40 of profit, two different percentages because the denominator changed underneath it.
Drop the cost to $30 on the same $100 price and the gap widens sharply: profit rises to $70, margin becomes 70% of price, but markup jumps to 233.3% of cost. The cheaper the item relative to what it sells for, the further markup outruns margin — exactly why quoting one number as if it were the other gets more dangerous, not less, on the highest-margin goods.
Questions
Why are margin and markup different numbers for the same sale?
Both start from the same profit — price minus cost — but that one figure gets set against two different bases: margin compares it to price, markup compares it to cost. Since price runs higher than cost on any profitable sale, markup always reads as the bigger percentage. On a $60 item sold for $100, a 40% margin sits beside a 66.7% markup: one profit, two yardsticks.
What is keystone pricing, and how does it map to margin?
Keystone pricing means doubling the cost to set the price — a $30 item becomes $60. That is a 100% markup, but only a 50% margin, because the $30 profit is half of the $60 price, not the full cost. A retailer quoting keystone as '100%' is speaking markup even on the days they mean to be speaking margin.
Is a 40% margin the same as a 40% markup?
No. A 40% margin on a $100 price leaves $40 of profit — the golden case above. A 40% markup on the same $60 cost leaves only $24 of profit, pricing the item at $84, not $100. Confusing the two on a single SKU can quietly cut real profit by double digits without any line item ever looking wrong.
How much does the gap between margin and markup widen as pricing gets more aggressive?
It grows without limit as cost shrinks relative to price. A $60 cost on a $100 price is a 40% margin against a 66.7% markup, roughly a 27-point gap. Drop the cost to $30 on the same $100 price and margin rises to 70% while markup jumps to 233.3%, a gap of over 160 points — high-margin goods are exactly where mixing the two terms costs the most.
Which figure belongs on a purchase order or a price tag — margin or markup?
Neither term is universal, so state which one is meant. Wholesale and manufacturing conversations often run in markup, because cost is the number a buyer already knows. Retail and financial reporting usually run in margin, because price is the reference point everyone downstream compares against. Writing '40%' alone on either document invites the other side to guess wrong.
Can markup ever be a smaller percentage than margin?
No, not for a profitable sale. Cost is always the smaller base and price the larger one, so setting the same profit over cost (markup) yields a bigger percentage than setting it over price (margin) every time price exceeds cost. The two converge only at zero profit, where price equals cost and both percentages read 0%.
References
- U.S. Small Business Administration — manage your business finances
- IRS — Publication 334, Tax Guide for Small Business
Read this first: This instrument shows arithmetic, not advice. Real offers add fees, taxes and terms that vary by lender and place — verify the figures against your actual paperwork before deciding anything.