Discount Calculator
Enter a positive price and discount percentages between 0 and 100.
Free discount calculator that stacks multiple sequential discounts correctly (20% off then an extra 10% off is 28% total, not 30%) and adds sales tax on the final price — we checked a widely used online discount calculator directly and it only handles a single discount, explicitly pointing you elsewhere for stacking.
How it works
- Enter the original price and list each discount percentage on its own line, applied in order
- Add an optional sales tax percentage for the final price
- See the price after discounts, total saved, effective combined discount rate, and the tax-included final price
Frequently asked questions
Why isn't 20% + 10% the same as 30% off?
Stacked discounts apply one after the other, each to what's left of the price — not both to the original price at once. $100 at 20% off is $80; take another 10% off that $80 and you land at $72, a 28% total discount, not 30%. We checked a widely used online discount calculator directly and it doesn't support stacking at all, sending you to a separate tool instead.
Can I add sales tax after the discount?
Yes — enter a tax percentage and it's applied to the already-discounted price, giving you the real final price you'd pay at checkout.
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20% off, then an extra 10% off, is not 30% off. It's 28%.
A popular discount calculator doesn't even try to handle this — it explicitly sends you elsewhere for stacked discounts, calling the math 'more confusing.'
2026-09-01Update history
- 2026-09-01 Added: a cover image (a price tag peeling back to reveal a second, smaller percentage tag stacked underneath) — used as the card thumbnail, social share image, and blog title image.
- 2026-09-01 Launched: discount calculator (no button) — stacks any number of sequential discounts correctly, shows the effective combined rate, and adds optional sales tax on the final price. Entirely client-side.