Know your margin before the Black Friday discount
Enter a price, a cost and your fees. See what each sale earns after the discount, how many extra sales it takes to break even, and the deepest discount you can afford.
Free. Your numbers stay on your device.
Your results
Discount ladder
What each common discount does to profit and how many extra sales it asks for.
All your products at this discount
Totals use your sales at full price for each product.
Keep your numbers
The CSV holds every product with the 10 to 40% ladder, ready for a spreadsheet. The summary prints on one page.
How the numbers are worked out
- Profit per saleThe sale price, minus your unit cost, minus fees (a percent of the sale price plus any fixed fee), minus shipping you pay.
- MarginProfit divided by the sale price. A 36.8% margin means you keep about 37 of every 100 you take in.
- Extra sales to break evenYour full-price profit across your usual sales, divided by the profit per sale at the discount, rounded up. When a discounted sale loses money, no number of sales fixes it.
- Deepest discountThe lowest sale price at which your margin still equals your minimum, rounded up to the next cent and shown as a percent off.
What to look for before you promote
- Profit drops faster than the price. Cost, fixed fees and shipping stay the same when the price falls, so 20% off can take far more than 20% from the profit on each sale.
- Test the extra sales number. If you would need triple your usual volume, the discount probably costs more than it earns. Check it against your stock and your honest forecast.
- Use the ladder. Choose the shallowest discount that still looks like a deal, then round the sale price to a figure that reads cleanly.
- Keep a floor. The deepest-discount figure is a stop line for codes, bundles and free-shipping offers that stack on top.
Free. Your figures stay in this page.
Questions people ask
What margin should I keep during Black Friday?
There is no single right number. Pick the lowest margin that still covers your time, returns and ads, enter it as your minimum, and the calculator shows the deepest discount that respects it.
Is margin the same as markup?
No. Margin is profit as a share of the sale price. Markup is profit as a share of cost. A product bought for 10 and sold for 20 has a 100% markup and a 50% margin.
Should I count shipping and returns?
Count shipping whenever you pay for it, and enter 0 when the customer covers it. For returns, add a small allowance to the unit cost so the margin reflects the orders that come back.
Are my numbers saved or sent anywhere?
No. The sums happen in your browser, and the CSV and the printable page are made on your device.