How to calculate sale price and savings
Turn a percentage or fixed coupon into a transparent sale price, savings amount, and effective discount.
Read guideUnderstand every price stage
Discount guides without hidden checkout assumptions
Three guides explain ordinary sale price, ordered discounts, tax-after-discount, and display rounding without claiming merchant or regional authority.
20% + 10% discounts = 28%, not 30%
Successive 20% and 10% discounts leave $72 from each $100: an effective 28% discount, not 30%. Check the formula and coupon order.
Read guideDiscount before tax and honest rounding
Keep discount, user-supplied tax, exact arithmetic, and merchant checkout rules in separate visible stages.
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