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Enter the original price and discount to see the sale price and your savings instantly. Add a second (coupon) discount and sales tax for the true out-the-door total.
The sale price is price × (1 − discount %) and savings are price × discount %. Stacked discounts multiply, they don\u2019t add: a 20% sale plus a 10% coupon is price × 0.80 × 0.90, an effective 28% off — not 30%. Tax is applied last, on the final discounted price: total = sale price × (1 + tax %). Worked example: $200 with 20% off and a 10% coupon → $200 × 0.80 = $160, then × 0.90 = $144.00 sale price; savings $56.00 (28% off). With 8% sales tax: $144 × 1.08 = $155.52 out the door. Results are rounded to the nearest cent.
Because the second discount applies to the already-discounted price, not the original. 0.80 × 0.90 = 0.72, so you pay 72% of the original — 28% off. Stores advertise \u201can extra 10% off\u201d precisely because it sounds bigger than it is.
After — in every US state, sales tax applies to the price you actually pay. The calculator applies tax to the final discounted price.
Divide the sale price by (1 − discount): a $144 item at 28% off was $144 ÷ 0.72 = $200.