US marketplace. Fee figures reflect Amazon’s published 2026 rate cards, last verified August 2026.
Markup is calculated on cost. Margin is calculated on selling price. A 40% markup on a $10 product gives a $14 price and a 28.6% margin — not 40%. The two figures are never equal above zero, and the gap widens as the numbers rise: a 100% markup is a 50% margin, and a 300% markup is a 75% margin. Sellers who set prices with a markup rule and then report the same number as their margin overstate profitability on every single SKU.
This is not a rounding error. On a catalogue priced with a 50% markup rule, the seller believes they are running a 50% margin business when they are running a 33% margin business. That is a 17-point gap applied to every unit, before Amazon has charged a single fee. It is one of the most common and most expensive arithmetic errors in ecommerce, and it survives because both numbers are described with the same word — “percent” — and both feel like they mean the same thing.
What is the actual difference between markup and margin?
Both measure the same dollar amount of profit. They differ only in what they divide it by.
| Markup | Margin | |
|---|---|---|
| Formula | (Price − Cost) ÷ Cost | (Price − Cost) ÷ Price |
| Denominator | What you paid | What the customer paid |
| Maximum value | Unlimited | Capped at 100% |
| Used for | Setting a price from a known cost | Reporting profitability, comparing SKUs |
| Who uses it | Buyers, sourcing agents, wholesalers | Accountants, investors, marketplace dashboards |
On a product costing $10 and selling for $14, the gross profit is $4 either way. Markup is $4 ÷ $10 = 40%. Margin is $4 ÷ $14 = 28.6%. Same four dollars, two different percentages, and only one of them is the number your P&L will show.
What is the markup-to-margin conversion table?
Keep this where you price products. The relationship is fixed and worth memorising at the common points.
| Markup | Resulting margin | Price on a $10 cost |
|---|---|---|
| 10% | 9.1% | $11.00 |
| 20% | 16.7% | $12.00 |
| 25% | 20.0% | $12.50 |
| 30% | 23.1% | $13.00 |
| 40% | 28.6% | $14.00 |
| 50% | 33.3% | $15.00 |
| 60% | 37.5% | $16.00 |
| 75% | 42.9% | $17.50 |
| 100% | 50.0% | $20.00 |
| 150% | 60.0% | $25.00 |
| 200% | 66.7% | $30.00 |
| 300% | 75.0% | $40.00 |
| 400% | 80.0% | $50.00 |
The two conversion formulas:
- Margin from markup: Markup ÷ (1 + Markup)
- Markup from margin: Margin ÷ (1 − Margin)
So a 35% target margin requires a markup of 0.35 ÷ 0.65 = 53.8%. On a $10 cost, that is a $15.38 price.
How do you price backwards from a target margin?
Markup thinking starts at cost and pushes upward. Margin thinking starts at the margin you need and works out the price. The second is the correct direction for an Amazon seller, because your fees are a percentage of price — which means price and cost are not independent.
The formula is Price = Cost ÷ (1 − Target margin).
Target a 40% gross margin on a $10 landed cost: $10 ÷ 0.60 = $16.67. Applying a 40% markup instead would have given you $14.00 and a 28.6% margin — a price $2.67 too low, and 11.4 margin points surrendered per unit.
Why does this get worse on Amazon specifically?
In traditional retail, markup-based pricing at least produces a stable, if misnamed, margin. On Amazon it does not, because the referral fee is charged on the selling price. Every dollar you add to the price hands 15% of that dollar straight back to Amazon, so the price required to hit a net margin target is higher than the naive calculation suggests.
The correct formula when a percentage fee applies is:
Price = (Cost + fixed per-unit fees) ÷ (1 − target margin − referral fee rate)
Take a $10 landed cost and a large standard-size product at 1.25–1.5 lb. In the $10–$50 price band the 2026 fulfillment fee is $5.42, or $5.61 with the 3.5% fuel and logistics surcharge that applies from April 17, 2026. Referral fee 15%, target net margin 20%:
Price = ($10.00 + $5.61) ÷ (1 − 0.20 − 0.15) = $15.61 ÷ 0.65 = $24.02
Check it: revenue $24.02, less referral fee $3.60, less fulfillment $5.61, less COGS $10.00 = $4.81 profit, which is 20.0% of $24.02. Correct.
Now watch what a markup rule does to the same product. A seller applying a common “3× cost” wholesale rule prices at $30.00: $30.00 − $4.50 referral − $5.61 fulfillment − $10.00 COGS = $9.89, or 33.0%. Fine. But apply “2× cost” to the same product — $20.00 — and you get $20.00 − $3.00 − $5.61 − $10.00 = $1.39, a 7.0% margin, before advertising, storage, or returns. The multiplier rule gave no warning that one of those two prices was viable and the other was not.
Watch the price bands
A 2026 wrinkle that breaks markup rules further: since January 15, 2026 Amazon publishes fulfillment fees in three price bands — under $10, $10 to $50, and over $50. Items under $10 qualify automatically for Low Price FBA, worth an average $0.86 per unit.
This means the fee is not independent of the price you set. A product priced at $9.99 pays a lower fulfillment fee than the same product at $10.00, and a product moving from $49.99 to $50.00 pays more. On thin-margin items the band boundary can be worth more than the price change itself, which is exactly the kind of discontinuity a fixed multiplier cannot see.
What does the error cost across a catalogue?
A seller doing $600,000 in annual revenue believes they run a 45% gross margin because they price everything at a 45% markup. Their actual gross margin is 31%.
| Believed (45% margin) | Actual (45% markup = 31% margin) | |
|---|---|---|
| Revenue | $600,000 | $600,000 |
| Gross profit | $270,000 | $186,000 |
| Amazon fees + ads (assume 32% of revenue) | −$192,000 | −$192,000 |
| Fixed costs | −$48,000 | −$48,000 |
| Result | $30,000 profit | −$54,000 loss |
An $84,000 swing produced entirely by a denominator. And because the seller’s mental model says the business is profitable, the natural response to a cash shortfall is to buy more inventory and scale — which accelerates the loss.
Common mistakes
- Taking a supplier’s “margin” claim at face value. Wholesalers and sourcing agents quote in markup because it makes the number look bigger. When a supplier says a product “gives you 50%,” ask which denominator. It is usually markup, so the real margin is 33%.
- Setting spreadsheet formulas as cost × (1 + margin). This computes a markup, not a margin. The correct formula is cost ÷ (1 − margin).
- Applying one blanket multiplier across the catalogue. A 3× rule works for a light $8 item and fails for a heavy $40 item, because FBA fulfillment fees are per-unit dollars, not percentages. Two products with identical markup can have wildly different margins.
- Discounting off the markup. A 20% off promotion on a product carrying a 25% markup (20% margin) leaves essentially nothing. Discounts consume margin, not markup, so always run them against the margin figure.
- Ignoring the fee price bands. A markup rule that lands a product at $10.00 rather than $9.99 can cost more in fulfillment fee than the extra penny earns.
- Mixing the two in one report. If sourcing works in markup and finance works in margin, every meeting compares incompatible numbers. Pick margin for all reporting and convert at the point of sourcing.
Once fees, storage, returns, and advertising enter the picture, the margin that matters is not the gross figure at all — it is what survives after every Amazon deduction on a per-SKU basis. Platforms like sellerboard compute that from actual settlement data, which is the only reliable way to check whether the price you set from a target margin is delivering it.
Frequently asked questions
Can margin ever exceed 100%?
No. Margin is profit as a share of price, so it approaches 100% only as cost approaches zero. Markup has no ceiling — a $1 cost sold at $50 is a 4,900% markup and a 98% margin.
Which should I use for pricing decisions?
Use margin. Set the margin you need, then derive the price with Price = Cost ÷ (1 − margin), adjusted for the referral fee rate and any fixed per-unit fees if selling on a marketplace. Markup is only convenient when you already know the cost and want a fast price; it is not a reporting metric.
Why do wholesalers and retailers still quote markup?
Because they price from cost. A buyer looking at a purchase order knows the cost and needs a price fast, and multiplying is quicker than dividing. The convention is fine internally, but it becomes a problem the moment the number is described as a margin.
What markup do I need for a 30% margin?
42.9%. Use Markup = Margin ÷ (1 − Margin): 0.30 ÷ 0.70 = 0.429.
Does this apply to net margin as well as gross?
Yes, and the gap is larger, because net margin is calculated on price after every fee. If you price from a markup rule and then report net margin, you compound the denominator error with an incomplete cost stack.
