A discount calculator answers two questions: what will I actually pay, and how much am I saving? It matters most when discounts stack. "25% off, plus an extra 10%" is not 35% off, and this calculator shows the real figure.
How it works
Multiply the original price by (1 − discount). 25% off $80 is $80 × 0.75 = $60.
A second discount applies to the already-reduced price, not the original. An extra 10% off $60 is $60 × 0.90 = $54. Stacked discounts combine as 1 − (1 − d₁) × (1 − d₂), so 25% and 10% together are 32.5%, not 35%.
Sales tax or VAT is normally charged on the discounted price, so it's added last. If your prices already include VAT, leave tax at 0.
If you're setting a discount rather than taking one, check what it does to your profit. A 20% discount on a product with a 40% margin cuts the profit on each sale in half. The Margin vs Markup Calculator shows that side.
A worked example
A jacket costs $80. It's 25% off, and there's an extra 10% off sale items. 25% off brings it to $60, and 10% off that brings it to $54. You save $26, which is a 32.5% total discount, not 35%.
Questions people ask
How do I calculate a discount?
Multiply the price by the discount percentage and subtract it. For 30% off $50: $50 × 0.30 = $15 off, so you pay $35. Or in one step: $50 × 0.70 = $35.
Is 20% off plus 10% off the same as 30% off?
No. The second discount applies to the reduced price, so 20% then 10% is 28% in total: $100 becomes $80, then $72. The order of the two discounts doesn't change the result.
How do I work out the original price from a sale price?
Divide the sale price by (1 − discount). If something costs $60 after 25% off, the original price was $60 ÷ 0.75 = $80.
Is tax charged before or after the discount?
In most places, tax is charged on the price after discounts from the seller. Manufacturer coupons can be treated differently in some US states, so check the receipt if the numbers don't match.
How do I calculate the percentage discount between two prices?
Subtract the new price from the old, divide by the old price and multiply by 100. From $80 to $54 is $26 ÷ $80 = 32.5% off. The Percentage Change Calculator does this for any two numbers.