Enter a price and percent off to get the sale price and savings instantly. Add your item cost to see the profit margin left after the discount, so you never run a promotion at a loss.
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Sale Price after 15% off
Healthy margin left after this discount.
A discount calculator takes an original price and a percentage off, then works out the sale price and how much money is saved. This one goes a step further for sellers: enter your item cost and it also shows the profit margin left after the discount, so you can see whether a promotion is still profitable before you launch it. For anyone selling across Shopee, Lazada, TikTok Shop, Amazon, or Shopify, that margin view is the difference between a promotion that drives volume and one that quietly loses money on every order.
The discount formula is: Sale Price = Original Price × (1 − Discount% / 100). For example, a $30 product at 15% off becomes $30 × (1 − 0.15) = $25.50, so you save $4.50. To find the amount saved directly, use Savings = Original Price × Discount% / 100. This calculator does both instantly and lets you flip the logic to work out an unknown discount percentage too.
If you know the original price and the sale price but not the percentage, use: Discount % = ((Original Price − Sale Price) / Original Price) × 100. For example, a product marked down from $80 to $48 is (($80 − $48) / $80) × 100 = 40% off. Switch to Find the Discount % mode above and the calculator solves it for you, then still shows your margin after the markdown if you add a cost.
Margin after discount is the profit margin left once the promotion price is applied: Margin After Discount = ((Sale Price − Item Cost) / Sale Price) × 100. It matters because a discount always comes out of your margin, not your cost. A product that costs $12 and normally sells for $30 has a 60% margin, but a 15% discount drops the sale price to $25.50 and the margin to 52.9%. Push the discount to 40% and the sale price falls to $18, leaving a 33% margin, and a deeper cut can wipe the margin out entirely. Always check the margin figure before committing to a campaign price. If you also sell on marketplaces, remember that platform fees come off on top of the discount, so your real take-home is lower still.
Actionable Insight: Set a floor margin (for example, 20%) and never let a promotion price drop below it. If a preset above turns the verdict red, the discount is selling below cost, which only makes sense for genuine clearance of dead stock.
Flash sales, vouchers, and campaign discounts are how you win visibility on Shopee, Lazada, and TikTok Shop, but each channel runs its own promotions on its own calendar. When the same SKU is discounted in several places at once, it is easy to lose track of the true selling price and margin per channel. A multichannel platform keeps one price and stock view across every storefront, so a promotion in one place does not oversell or mis-price the same product somewhere else. You can also plan recurring markdowns in OneCart with bulk discounts instead of editing prices marketplace by marketplace.
The biggest mistake is discounting off the sticker price without checking the cost underneath it. Others include stacking a voucher on top of an already-reduced price until the order loses money, forgetting that marketplace commission and payment fees still apply after the discount, and discounting healthy sellers that would have sold at full price anyway. Use this calculator to model the margin first, then use a markup calculator to set an original price with enough headroom to discount from in the first place.
Multiply the price by 0.80 (which is 1 − 0.20). A $45 item at 20% off is $45 × 0.80 = $36, saving you $9. Enter 45 and 20 in the calculator above to confirm, and add your cost to see the margin that is left.
No. A discount is taken off the selling price, so its effect on margin depends on your cost. A 15% price discount on a 60% margin product cuts the margin to about 53%, not to 45%. That is why checking the margin-after-discount figure matters rather than assuming the percentages line up.
There is no single number, because it depends on your cost and the fees on each channel. A practical rule is to set a minimum acceptable margin (many sellers use 15 to 20%) and cap every promotion so the sale price never falls below it. The verdict line above flags when a discount pushes you under a thin margin or below cost.
Yes. Switch to Find the Discount % mode, enter the original and sale prices, and the calculator returns the exact percentage off, so you can confirm whether an advertised deal is as deep as it claims.
OneCart keeps one price, stock, and margin view across Shopee, Lazada, TikTok Shop, Amazon, Shopify, and more, so your discounts stay profitable on every channel.
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