Discount margin impact — how a sale changes profit
Enter your full price, unit cost, and discount percent. See the sale price, profit before and after, margin after the cut, and how many discounted units it takes to match the profit from one full-price sale.
Results
Sale price: 32
Profit at full price: 18
Profit at sale price: 10
Margin after discount: 31.3%
Sale units to match one full-price profit: 2 (extra units: 1)
Formula
sale=price×(1−discount); units=ceil(profitBefore÷profitAfter)
How the numbers are calculated
- Sale price = 40 × (1−0.2) = 32
- Profit at sale price = 32 − 22 = 10
A “20% off” badge is easy to post and hard to earn back. Shoppers see the percent; your bank account sees a thinner contribution on every unit that converts because of the badge.
This page shows the sale price, profit before and after, and the recovery math: how many discounted units replace the profit from one full-price sale. When sale profit hits zero or goes negative, it says so plainly — volume cannot fix a price at or below cost.
Use it before holiday codes, flash sales, and “first order” coupons. If recovery volume looks unrealistic for your traffic, shrink the discount or shorten the window instead of hoping the algorithm will fill the gap.
How to use
- Enter full price and unit cost
- Set the discount % you plan to advertise
- Read sale profit and how many sale units recover one full-price profit
Why this calculator
- Makes sale price and post-discount margin obvious
- Shows how many sale units replace one full-price profit
- Flags discounts that sell below cost
Good for
- Holiday and seasonal sales
- Coupon and code planning
- Clearance price checks
Tips
- If profit after the discount is ≤ 0, skip or redesign the offer.
- Fold fees into cost when you want a conservative stress test.
- After the sale, re-check break-even with the weaker contribution.
Examples
| Input | Output | Note |
|---|---|---|
| $40 price, $22 cost, 20% off | Sale $32; need 2 sale units to match 1 full-price profit | Full-price profit $18 → sale profit $10 → ceil(18÷10)=2 |
| $40 price, $22 cost, 50% off | Sale $20 — at or below cost; the page flags a loss | Deep cuts need a clearance reason, not a “traffic” excuse alone |
Discount FAQ
- What does “extra units” mean?
- If one full-price sale made $18 and the discounted sale makes $10, you need two sale units to match that $18 — one of them is the “extra” unit beyond the first.
- Should fees go in cost?
- For a harsher test, yes: add average marketplace fees into unit cost so the discount cannot pretend fees disappeared.
- Still setting the full price?
- Start from Craft pricing, then stress-test the promo percentage here before you hit publish.
- Does this replace break-even?
- No. Break-even asks how many units cover fixed costs; this page asks how a temporary price cut changes per-unit profit. Use both when a sale weekend is on the calendar.