Explanation · Money
A 30% markup is not a 30% margin
The same sale can produce two different percentages. Learn which amount each uses and why the costs you include matter just as much.
You buy something for $70 and sell it for $100. There is $30 between those numbers. One person calls that a 30% margin; another calls it a 43% markup. Both can be describing the same transaction because they are dividing by different amounts.
Confusing the two can produce a price that looks right in a conversation and disappoints in the accounts. The problem gets larger when people also mean different things by cost: one includes freight, another includes packaging, and a third uses only the supplier's headline price.
What this means for your business
Whenever someone proposes a percentage, ask two questions: percentage of what, and after which costs? Write the answers beside the number. This matters in price lists, quotes, supplier comparisons and discussions with a bookkeeper or manager.
The calculation should help you understand what a sale leaves to cover the rest of the business. A percentage without a cost definition cannot do that reliably. A higher percentage also does not automatically produce more total dollars if volume, order size or the work required changes.
The same $30, two different percentages
$70 included cost$30 left above that cost
Margin compares with the whole price
$30 ÷ $100 = 30%
Of every $1 the customer pays, 30¢ remains above the included cost.
Markup compares with the cost
$30 ÷ $70 ≈ 42.9%
For every $1 of included cost, about 43¢ has been added to set the price.
The $30 is not necessarily final profit. Other business costs may still need to be paid.
Using a $70 cost and $100 selling price:
- Margin on this defined cost basis is ($100 − $70) ÷ $100 = 30%.
- Markup on that cost is ($100 − $70) ÷ $70 = approximately 42.9%.
Margin uses the selling price as its denominator. Markup uses cost. If you add a 30% markup to $70, the price is $91. The $21 difference is only about 23.1% of that $91 price.
“Denominator” just means the number you divide by. For margin, the question is: out of each dollar the customer pays, how much remains above the costs we included? For markup, it is: how much did we add for each dollar of that cost? The money earned has not changed. The reference amount has.
On a basic calculator, subtract $70 from $100 to get $30. For margin, divide 30 by 100 to get 0.30, then multiply by 100 to display 30%. For markup, divide 30 by 70 to get about 0.4286, then multiply by 100 to display about 42.9%.
| Method | Cost used | Selling price | Dollars left above that cost | Margin |
|---|---|---|---|---|
| Add a 30% markup | $70 | $91 | $21 | 23.1% |
| Set a 30% margin | $70 | $100 | $30 | 30.0% |
To calculate a price for a desired margin on a known dollar cost, divide the cost by one minus the desired margin expressed as a decimal. Here, $70 ÷ (1 − 0.30) = $100. This simple formula assumes the included dollar cost does not itself change with the price.
Why divide by 0.70? A 30% margin means the included cost must occupy the other 70% of the price. You already know that 70% is $70, so the full price must be $100. Adding 30% to cost answers a different question, which is why it produces $91.
Give the percentage a name
Margin is a relationship between an amount left and a selling price. The name tells you which expenses have already been subtracted.
| Measure | What it describes | What it does not establish |
|---|---|---|
| Gross margin | Sales less the cost of sales used in the accounts, expressed as a share of sales | The result after every operating expense |
| Contribution margin | Sales less the costs that vary with those sales, expressed as a share of sales | Whether the amount covers fixed costs |
| Net profit margin | The final profit reported for a period, divided by that period's sales | How much cash is available to withdraw |
The $30 above the example's $70 cost is only a defined-cost difference until you know what that $70 includes. Calling it “profit” without that explanation could lead someone to spend money the rest of the business still needs. See how sales must cover the cost of being open for the next step.
Decide which costs belong in your calculation
For gross margin in financial reporting, the cost of sales follows the accounting policy used in your books. Contribution is a management calculation that deducts the costs that vary with the sale. Those measures can differ, especially where labor, processing and delivery are classified differently.
The SEC's guide to financial statements describes gross profit as revenue less the cost of sales, before other operating expenses. That is why gross profit should not be read as the business's final profit.
For a pricing decision, write an explicit cost list. Does it include delivery to you, packaging, transaction charges, marketplace commissions, expected waste and the labor that changes with the sale? Keep costs already counted in another line from appearing twice.
If a fee is a percentage of the selling price, it cannot be treated as a fixed dollar cost across different prices. At a $100 price, a 3% fee is $3; at $110 it is $3.30. Calculate the fee at each proposed price before comparing what remains.
For example, with $70 of fixed-dollar cost per item, a fee of 3% of the selling price, and a target of 30% left after both, only 67% of the price is available for the $70 cost. The calculation becomes $70 ÷ (1 − 0.30 − 0.03), or about $104.48. At that price the fee is about $3.13 and roughly $31.35 remains, allowing for rounding. This assumes the fee applies to the selling price alone and there are no other charges. If the real fee includes a per-transaction amount or uses another base, include that too. For a positive dollar cost, the target margin and percentage fee must add to less than 100% for this formula to produce a workable positive price.
A restaurant example: ingredient margin is only one view
Imagine a meal sold for $20, excluding sales tax collected for the government. Ingredients cost $6. The $14 difference is 70% of the selling price. That calculation is useful for understanding ingredients, but it has not paid kitchen labor, rent, utilities or many other costs.
Now imagine the same meal sold through a channel charging a $4 fee and requiring $1 of packaging. After ingredients, that fee and packaging, $9 remains. That is 45% of the $20 price before any other costs. Calling both sales a 70% margin would hide the difference you need for the channel decision.
These amounts are invented for the example, not industry benchmarks. A different channel may also bring incremental orders or require less front-of-house work. Compare the costs and capacity actually affected rather than concluding that one channel is always better.
Watch what happens when costs move
Suppose the $70 item rises to $77 while the selling price stays $100. The margin on that cost basis falls from 30% to 23%. To restore 30% with the new $77 cost, the price would be $110, before considering any percentage-based charges.
That is a fall of seven percentage points: 30 minus 23. The dollars left fell from $30 to $23, a reduction of about 23.3% relative to the original $30. “Seven percentage points” and “seven percent” would describe different changes here.
That calculation describes the price needed to preserve a percentage. It does not predict whether buyers will accept it. You still need to examine demand, alternatives and the contribution dollars produced at different volumes. Sometimes a smaller margin on a reliable, efficient sale can be more useful than a higher margin on a slow-moving item.
Make the definition travel with the number
For your important products or services, record the net selling price, the cost items included, dollars left, margin and markup. Date the supplier costs and note the channel. Use the same definition in the owner's review, the manager's report and the price calculator.
When two reports disagree, reconcile the definitions before deciding either one is wrong. Discounts, refunds, tax treatment, timing and cost classification can all create differences. A useful review ends with a shared explanation and a decision, not just a corrected percentage.
Sources and further reading
The SEC's financial-statement guide provides the accounting context for gross profit and operating expenses; consulted September 20, 2026. The pricing arithmetic and examples are Black Lentil teaching material. Continue with the price increase guide and the price change calculator.