Profit and pricing
Discount Impact Calculator
See how a discount changes profit per sale, total profit, and the number of sales needed to match your full-price baseline. Enter your platform fee directly - no rates are built in.
Formula
- Discounted price = Regular price * (1 - Discount %)
- Profit per sale = Price * (1 - Platform fee %) - Fixed fee - Variable cost
- Total profit = Profit per sale * Number of sales
- Profit difference = Discounted total profit - Baseline total profit
- Sales needed at discounted price to match baseline = Baseline total profit / Discounted profit per sale
- Extra sales needed = Sales needed - Expected discounted sales (or 0 if already exceeded)
Examples
- A $29 product discounted 20% to $23.20 with a 10% platform fee and $0.50 fixed fee earns about $20.38 per sale instead of $25.60 - a $5.22 drop per sale.
- If baseline is 100 full-price sales and you expect 150 discounted sales, the discount can still grow total profit even though each sale earns less.
- On a $9 product, a 20% discount with $0.50 fixed fee per sale cuts net profit much more sharply than the same discount on a $99 product, because the fixed fee is a bigger share of revenue.
When to use this calculator
- Decide whether a planned promotion (Black Friday, launch sale, holiday bundle) is worth running.
- Set a minimum extra-sales target a discount must beat to be worth it.
- Compare two discount sizes side-by-side by changing the discount percent.
Common mistakes
- Comparing only revenue, not profit; a discount can raise revenue while cutting profit.
- Ignoring fixed per-sale fees, which hurt low-price discounts most.
- Assuming a discount automatically lifts sales enough to compensate; this calculator forces you to supply the expected volume, not guess it.
Frequently asked questions
What does this calculator estimate?
It estimates the direct, per-sale and total profit impact of running a discount, and how many discounted sales you'd need to match your full-price baseline profit. You supply the baseline sales, the expected discounted sales, the platform fee, and the fixed per-sale fee - the calculator does the math, but does not predict how much a discount will lift sales.
How is profit difference calculated?
Profit per sale at each price = Price * (1 - Platform fee %) - Fixed fee per sale - Variable cost. Total profit at each price = Profit per sale * Number of sales. Profit difference = Discounted total - Baseline total. A positive number means the discount grows total profit at your expected sales volume; a negative number means it shrinks total profit.
How is the 'sales needed' number calculated?
It is Baseline total profit divided by Discounted profit per sale, rounded up. If you can hit that number of discounted sales, you match your full-price total profit. The 'extra sales needed' row is that number minus the discounted sales you already expect; if the result is zero or negative, your expected volume already matches or beats baseline.
Why do fixed per-sale fees hurt low-price discounts most?
A $0.50 fixed fee is about 5.6% of a $9 product but only 0.5% of a $99 product. Discounting a low-price product makes the fixed fee even larger as a share of revenue, so the effective fee rate climbs quickly. High-ticket products tolerate discounts much better in fee terms.
When does a discount lose money on every sale?
When Discounted price * (1 - Platform fee %) is smaller than Fixed fee + Variable cost. In that case, every additional discounted sale subtracts profit instead of adding it, and no amount of extra volume can make up for it. The calculator flags this case explicitly.
Should I avoid any discount that needs more sales than I expect?
Not always. A discount that needs more sales than expected still has real value if it brings in new customers who buy again later, reduces inventory holding cost, or supports a launch. This calculator only models the direct first-purchase profit; other benefits and costs are real but harder to estimate.
What about platform fees and payment processing?
Enter the combined platform plus payment processing fee in the Platform fee percentage field, and use Fixed fee per sale for any per-transaction flat fee. The Stripe Fee, PayPal Fee, and Platform Take-Home calculators can help you figure out the right blended rate for your situation before plugging it in here.
How is this different from the Break-Even Calculator?
Break-Even answers 'how many sales until total profit reaches zero given fixed costs?' This calculator answers 'how does a discount change profit per sale and total profit, and how many more sales do I need to match a specific baseline?' They are complementary: use Break-Even for product viability and this one for promotion decisions.
Related calculators
Sources and assumptions
- Platform fee and fixed fee are entered manually; no platform rates are built in, since this calculator is not platform-specific.
- Variable cost includes anything that scales per sale (cost of goods, per-unit production, drop-ship cost, etc.).
- Profit shown does NOT subtract fixed monthly costs, taxes, or marketing spend; pair this with the Profit Margin and Break-Even calculators for a full view.
Formula reviewed:
Last updated:
This calculator estimates the direct, per-sale impact of a discount. It does NOT predict how much a discount will lift conversion or sales volume; you supply both the baseline and expected discounted sales. Pair the result with Profit Margin and Break-Even for a fuller decision.