Formula used
Required volume multiplier = current gross margin divided by gross margin after the discount.
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Promotion tool
Discount Penalty Calculator
See how many more units a discount must sell before the promotion earns the same profit as your regular price.
Extra volume needed80%
Break-even units180
Unit profit left25.0%
Inputs
Your promo math
Use gross margin before discount and the proposed percent-off offer.
Your numbers stay in this browser. Free calculator inputs are not stored on our servers.
Volume lift required
80%
A 20% discount means you need 1.80x normal unit volume to make the same gross profit.
0% offMargin limitLoss zone
StatusAggressive volume hurdle
Extra units needed80
Discount formula
Original profit45.0%
Discounted profit25.0%
Required units180
- You need 80 extra units on top of your normal 100 units to match profit.
- Use the discount only if paid traffic, email, or inventory clearance can realistically create that volume lift.
Guide
How to use the discount profitability calculator
Use this before approving a flash sale, email promo, holiday discount, or clearance campaign.
Healthy benchmark
If a discount requires more than 50-100% extra unit volume, the promotion usually needs a strong strategic reason such as inventory clearance, first-purchase acquisition, or bundle attach rate.
Common mistakes
- Comparing revenue lift instead of contribution profit lift.
- Running a discount that is deeper than the product margin can support.
- Ignoring extra ad spend, support tickets, returns, and fulfillment pressure during the sale.
When this result matters
Use this before approving a flash sale, email promo, holiday discount, or clearance campaign.
The useful output is not just the final number. It is the margin of safety between your current plan and the point where the decision starts taking cash out of the business.
Example operator review
Start with the current numbers, change one assumption at a time, then write down the threshold you will not cross before committing spend, stock, payroll, or pricing changes.
Is the discount profitability calculator free?
Yes. You can use the calculator without an account. Clear Margins Pro is for saving scenario history, exporting CSV notes, and reviewing repeat decisions.
Where are my calculator inputs stored?
Free calculator inputs stay in your browser while you use the page and are not stored on Clear Margins servers.
What should I do after I get a result?
Treat the result as a decision floor, then compare it with the paired risk: pricing with ROAS, discounts with volume, inventory with runway, and hiring with capacity.