Discount profit impact is the change in total profit when a promotion lowers your margin per unit but, ideally, raises the number of units sold.
What is the Discount Profit Impact Calculator?
This free discount and promotion profit impact calculator shows whether a sale will actually make you money. Discounting is the easiest way to erode profit unnoticed; this tool reveals the volume lift a discount must achieve before it pays off.
How this calculator works
Enter your normal price, product cost, the discount percentage, your baseline units for the period, and the volume lift you expect from the promotion. The tool compares margin and profit before and during the promo, and calculates the volume lift needed just to break even.
How to read your result
The headline is the profit change from running the promo. The rows show margin per unit before and after, profit before and during, and the volume lift required to break even. If your expected lift is below the break-even lift, the discount loses money, so adjust the depth or the offer.
Work with a Shopify expert
If you discount often, we can build margin-safe offers and bundles instead. Talk to a Shopify expert.
This free discount profit impact calculator gives a fast, data-informed estimate; for wider industry context on discount profit impact, see Investopedia on contribution margin.
Break-even lift = profit before / discounted margin per unitFactors
Discount depth
Deeper discounts cut margin per unit sharply and raise the volume you need.
Product margin
Low-margin products need a much bigger volume lift to absorb a discount.
Expected volume lift
Your honest estimate of how much the promo increases units sold.
Baseline units
The normal volume the promotion is measured against.
- Free and instant - no sign-up required.
- Built for Shopify and ecommerce stores.
- Use real numbers to plan with confidence.
- Turn the result into action with CartCoders.
Related calculators
Planning a project usually means weighing more than one number. These tools cover the decisions next to this one:
- Profit Margin Calculator — profit per order
- Average Order Value Calculator — grow AOV
- Break-Even Point Calculator — units to break even
Frequently asked questions
How do I know if a discount is profitable?
Compare the profit you would make at the discounted margin and higher volume against your normal profit. This calculator shows the exact volume lift the discount needs just to break even.
Why are deep discounts risky?
A discount lowers margin on every unit, including the ones you would have sold anyway, so you need a large volume increase to make up the lost margin. Low-margin products are especially exposed.
What is a margin-safe alternative to discounting?
Bundles, gift-with-purchase, free-shipping thresholds, and volume offers can lift order value without cutting your unit margin as hard as a straight percentage discount.