Discount Calculator
Written by Thierno Sadou Diallo, formula verified per our methodology • Last checked on 9/3/2026
To calculate a price after a discount, multiply the original price by the discount percentage to get the discount amount, then subtract that amount from the original price. Example: €100 with a 20% discount gives €80 (discount amount: €20).
Explanation
A discount reduces a price by a certain percentage. The calculation happens in two steps: first work out the discount amount (original price × discount rate), then subtract it from the original price to get the final price — the same mechanism as the basic percentage calculator. It's the reverse operation of a markup: instead of adding a percentage, you remove one. To compare several successive discounts (for example two combined sales), each discount must be applied one after another on the already-reduced price, not simply added together as percentages: two 20% discounts applied one after the other do not add up to 40%, but to 36% overall.
Example: a 20% discount on a €100 item
Inputs
Original price: €100. Discount: 20%.
Calculation
First calculate the discount amount: €100 × 20% = 100 × 0.20 = €20. Then subtract that amount from the original price: €100 − €20 = €80.
Result
The discount amount is €20, for a final price of €80.
Frequently asked questions
Do two 20% discounts add up to a 40% discount?
No. Each discount applies to the price already reduced by the previous one. On €100, a first 20% discount gives €80; a second 20% discount on those €80 gives €64 — a total reduction of 36%, not 40%.
How do I calculate the discount percentage from the two prices?
If you know the original and final prices but not the discount rate, use our percentage calculator: the discount rate corresponds to the absolute value of the variation between the two prices.
Can the discount exceed 100%?
No, in this calculator a 100% discount means a free item (final price of €0). A higher percentage would give a negative price, which doesn't make sense for a commercial discount.
How do I find the original price from the sale price?
Divide the sale price by (1 − discount rate/100). For example, an item at €80 after a 20% discount had an original price of 80 ÷ (1 − 0.20) = 80 ÷ 0.80 = €100.