パーセントオフ計算ツール
The detailed guide below is currently available in English.
How stacked discounts work
Each percent-off step multiplies the running price by the share you still pay. After a discount of d%, the price becomes price × (1 − d ÷ 100), and a second discount applies to that reduced figure. So $200 marked 25% off drops to $150, and an extra 10% off lands on $150, giving $135 — a combined cut of 32.5%, not 35%. The only math after the discounts is sales tax, which most places charge on the discounted subtotal you actually pay.
よくある質問
Is 20% off then 20% off the same as 40% off?
No. Taking 20% off leaves 80% of the price, and the second 20% takes 80% of that, so you pay 0.8 × 0.8 = 64% — a 36% total cut. Enter both discounts above and the calculator does the compounding for you.
Should sales tax be added before or after the discount?
In most U.S. states, tax is charged on the amount you actually pay after store discounts, which is how this calculator applies it. A few jurisdictions tax the original price; if yours does, add the tax yourself on the pre-discount figure.