Discount calculator

Use the discount percentage, not the amount you pay

A 15% discount means you pay 85% of the original price. Enter 15 in Discount (% off), not 85 or 0.15. The tool accepts discounts from 0 to 100% with at most 1 decimal place. A value of 0 leaves the price unchanged; 100 makes the sale price zero.

Prices have no fixed currency. Enter both amounts in the same currency and omit symbols. The tool keeps up to 2 decimal places for prices, including when your currency or retailer normally uses whole units; you may need to apply the retailer’s own rounding rule afterward.

Calculate a sale price and savings

Suppose an item costs 1,000 and is 15% off. In Sale price, enter 1000 as Original price and 15 as the discount. The calculation is 1,000 × (1 − 15 ÷ 100), giving a sale price of 850 and savings of 150. These are illustrative amounts, not an advertised offer.

The savings amount is the difference between the displayed original and sale prices. For a price that lands between hundredths, the sale price is rounded to 2 decimal places and marked approximate. At tiny amounts, that rounded money difference may not reproduce the entered discount percentage exactly.

Find the discount from two prices

If you know an original price of 1,000 and a sale price of 850, choose Percentage discount. The difference of 150 divided by the original 1,000 is a 15% discount. The sale price must not exceed the original price, and the original price must be above zero.

The percentage shown here is rounded to at most 2 decimal places. To compare offers, keep both the percentage and the money saved in view: the same percentage off two differently priced items does not save the same amount.

Work back to the original price

For a sale price of 850 after 15% off, choose Original price and enter 850 and 15. Divide the sale price by the remaining 85%: 850 ÷ 0.85 = 1,000. Adding 15% to 850 would give a different answer, because that increase would use the sale price as its base.

A 100% discount cannot recover an original price: a zero sale price could have come from many original prices. Use a discount below 100% for this mode. If the recovered price exceeds 1,000,000,000,000, the tool asks you to check the inputs.

Reverse calculations use the price you enter. If a shop rounded its sale price or applied other adjustments, the recovered original price can differ from the price on its label. Treat it as a check of the stated numbers, not proof of a retailer’s pricing history.

Know what is outside this calculation

Each price must be from 0 to 1,000,000,000,000 with up to 2 decimal places. Use a decimal point and, if needed, correctly grouped commas such as 1,000. Currency symbols, negative amounts, units and scientific notation are not accepted.

This is a single-discount calculation. Two successive 20% discounts do not equal 40% off: 1,000 reduced by 20% becomes 800, then another 20% becomes 640. You can check the stages separately, but this page has no combined-offer or coupon-stacking mode. Tax, delivery fees, eligibility rules and fixed-amount vouchers also need separate checks.

The tool calculates in your browser and does not send or save the prices you enter. Copying a result places text on your system clipboard. Clearing the result does not clear clipboard history or syncing controlled by your device.

Sources

• Microsoft Support: Calculate percentagesBackground on percentage amounts, shares and changes. The input limits and rounding described here belong to this calculator.