Discount Calculator
Enter the original price and the percentage off. Add a second discount if the store stacks offers, and sales tax if it is charged at the till. You see the final price and exactly how much you save.
Enter your numbers to see the result.
How the sale price is calculated
The sale price is the original price multiplied by one minus the discount as a decimal. A 20% discount on 2,500 is 2,500 × 0.80 = 2,000, so you save 500. Tax, if any, is added after the discount, which is how most shops charge it.
Stacked discounts are not added together
When a store says 20% off, then an extra 10% off at checkout, the two do not make 30%. The second discount applies to the already reduced price. On 2,500 you get 2,500 × 0.80 × 0.90 = 1,800, a total saving of 28%, not 30%. Enter both discounts above and the calculator does this correctly.
Spotting a weak deal
A big percentage off a price that was inflated first is not a bargain. Check what the item usually costs and compare the final price, not the headline percentage. To compare two prices directly, use the percentage calculator in percentage change mode.
If you sell products
Deep discounts can erase your profit faster than you expect. Use the profit margin calculator to check that the sale price still leaves room above your cost.
Frequently asked questions
How do I calculate a discount?
Multiply the original price by the discount percentage divided by 100 to get the saving, then subtract it from the price. 20% off 2,500 saves 500 and leaves 2,000.
Do two discounts add up?
No. The second discount applies to the reduced price, so 20% then 10% equals a 28% total discount, not 30%.
Is tax added before or after the discount?
In most places tax is charged on the discounted price. If your store works differently, set the tax to 0 and add it yourself.
How do I find the original price from a sale price?
Divide the sale price by one minus the discount rate. If something costs 80 after 20% off, the original price was 80 divided by 0.80, which is 100.