Ecommerce promotion calculator
Discount Impact Calculator
See what a promotion does to per-unit profit—and exactly how many more units you must sell to make up the difference.
✓ Pricing inputs stay on this device✓ No signup✓ Instant results
Profit impact
Promotion economics
Required lift preserves total baseline profit; it is not a sales forecast.
Required sales lift59.5%
Discount sensitivity
These steps are calculation aids, not recommended promotion levels.
| Discount | Profit / unit | Required sales lift |
|---|---|---|
| 5.0% | $47.15 | 10.3% |
| 10.0% | $42.30 | 22.9% |
| 15.0% | $37.45 | 38.9% |
| 20.0% | $32.60 | 59.5% |
| 25.0% | $27.75 | 87.4% |
| 30.0% | $22.90 | 127.1% |
| 35.0% | $18.05 | 188.1% |
| 40.0% | $13.20 | 293.9% |
| 45.0% | $8.35 | 522.8% |
| 50.0% | $3.50 | 1,385.7% |
The discounted item remains profitable. Compare required lift with a realistic sales forecast.
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Pricing inputs stay on this device
All promotion calculations run locally in your browser. The values you enter are not uploaded or tied to an account.
Method
How discount profit impact is calculated
The calculator recomputes price-linked fees, compares profit per unit and then solves for the volume needed to preserve total profit.
1. Profit at each selling price
Fixed per-unit costs stay constant while percentage fees fall with the discounted price.
Unit profit = selling price − per-unit costs − price-based fees 2. Maximum break-even discount
The limit is the discount where unit profit reaches zero. Going further creates a unit loss.
Break-even price = per-unit costs ÷ (1 − fee rate) 3. Required sales lift
When both prices are profitable, divide original unit profit by discounted unit profit to get the required volume multiple.
Required units = baseline units × original unit profit ÷ discounted unit profit Why fee treatment matters
A percentage payment fee is charged on the actual discounted revenue, while product and fulfillment costs usually stay fixed per unit.
What the model does not predict
The calculation tells you the sales lift required to preserve profit. It does not predict whether customer demand will actually rise by that amount.
FAQ
Discount impact calculator FAQ
How much more do I need to sell after a discount?
Divide original profit per unit by discounted profit per unit. The result is the sales-volume multiple required to preserve the same total profit.
What is the maximum discount before losing money?
It is the point where the discounted price covers fixed per-unit costs plus percentage fees and leaves zero profit. A deeper discount creates a loss per unit.
Why do percentage fees change after discounting?
Payment and platform percentage fees are modeled on actual selling price, so their currency amount falls when price falls.
Can selling more fix a negative unit profit?
No. When every extra unit loses money, higher volume increases the total loss. The calculator therefore shows no finite required lift.
Should I use orders or individual products?
Use either one consistently. All price, cost and volume inputs must describe the same unit of analysis.
Does 321Kit store my pricing data?
No. Pricing and cost inputs stay in your browser and are not uploaded to 321Kit.