Profit Margin vs. Markup: Why They're Never the Same Number
The math showing exactly why margin and markup differ for the same sale, with a worked example and a conversion formula.
Margin and markup describe the exact same profit in dollar terms, but they're calculated against different bases — which means they're never equal (except at 0%), and confusing them is one of the most common small-business pricing mistakes.
The two formulas
Margin = (Revenue − Cost) / Revenue × 100 — profit as a percentage of what the customer paid.
Markup = (Revenue − Cost) / Cost × 100 — profit as a percentage of what it cost you.
Worked example
Buy a product for $150, sell it for $250. Profit is $100 either way. Margin: 100/250 × 100 = 40%. Markup: 100/150 × 100 = 66.7%. Same $100 profit, same sale — two very different-looking percentages, because the denominator changed from $250 (revenue) to $150 (cost).
Converting between them
Because they're both describing the same profit, there's a direct conversion: Markup% = Margin% / (100 − Margin%) × 100. Plugging in 40%: 40/(100−40) × 100 = 40/60 × 100 = 66.7% — confirming the two independently-calculated numbers above are consistent.
Why this trips up pricing decisions
If a business wants a 40% margin and mistakenly marks up cost by 40% instead (rather than the correct 66.7%), the actual margin achieved is much lower than intended. A $150-cost item marked up 40% sells for $210, giving margin (210−150)/210 × 100 ≈ 28.6% — nearly 11.4 percentage points short of the intended 40% margin target. At scale, across thousands of units, that gap represents real, unplanned lost profit.
Which one should you use?
Retail and finance conventionally talk in margin (percentage of revenue) because it directly ties to profitability metrics used in financial statements. Wholesalers and manufacturers more often talk in markup (percentage of cost) because it's simpler to apply directly on top of a known unit cost. Neither is "more correct" — they're just different lenses on the same profit.
Common mistakes to avoid
- Using markup and margin interchangeably in conversation, especially across departments (sales often thinks in margin, purchasing often thinks in markup)
- Forgetting that margin can never mathematically reach 100% (it approaches 100% only as cost approaches zero), while markup has no upper bound
- Applying an industry "typical margin" benchmark as if it were a markup figure, or vice versa, which silently misprices an entire product line
Calculate both numbers instantly with the margin calculator and markup calculator, or use the dedicated margin to markup converter.