Discount Margin Impact Calculator
Required volume rises steeply as margin falls.
Extra units needed
83%
margin falls to 30%
A 20% discount on a 44% margin needs 83% more units. The required uplift rises steeply as margin falls: the same discount on a 29% margin would need 222% more.
How the Discount Margin Impact Calculator works
The volume a discount needs rises steeply as margin falls. The same 20% discount needs 83% more units at a 44% margin and 300% more at a 25% one, which is why identical promotions succeed in one category and destroy another.
Also known as: how discounts affect margin · margin after discount · discount cost to profit
Not financial advice. Marketplace fees change, and they vary by country, plan and seller status. Every rate here is an editable default, not a quoted price, check the platform's current fee schedule before you price a product against it. This is not tax or business advice.
Frequently asked questions
How much volume does a discount need?
Margin divided by (margin minus discount). The formula is simple and the results are consistently larger than intuition suggests.
What happens to margin after a discount?
It falls faster than the discount, because the cost stays fixed while the price drops. A 44% margin with a 20% discount becomes 30%, not 24%.
Is there a discount that is always safe?
None. What is safe depends entirely on margin, and any discount approaching the margin destroys contribution regardless of volume.
How should I set a discount policy?
Work backwards from a maximum acceptable contribution per unit and enforce it as a floor in the platform. Discretionary discounting without a floor is how margin erodes without anyone deciding to erode it.