Free discount calculator. Find the sale price after a percentage discount, stack multiple discounts correctly, or work out the original price from a sale price.
A discount calculator finds the sale price after applying a percentage discount: Final Price = Original Price x (1 - Discount% / 100). Stacked discounts (e.g. 30% off, then an extra 20% off) are applied sequentially, not added together ā 30% + 20% stacked equals a 44% total discount, not 50%.
Last updated:
Discount Calculator
Calculating a discount is straightforward: multiply the original price by the discount percentage (as a decimal) to get the discount amount, then subtract that from the original price. A $50 item with a 15% discount saves $7.50, bringing the price to $42.50.
Common Mistake
The mistake: assuming "30% off, then an extra 20% off" equals 50% off the original price. It does not ā each discount is applied to the price remaining after the previous discount, not to the original price.
The correct math: $100 with 30% off becomes $70. An extra 20% off $70 is $14, leaving $56. The combined effect is a 44% discount off the original $100 ā six percentage points less than simply adding 30% and 20%.
Reverse Calculation
If you know the sale price and the discount percentage, you can work backward to the original price by dividing the sale price by (1 minus the discount as a decimal). For example, a $56 sale price after a 30% discount means the original price was $56 / 0.70 = $80.
This is useful for verifying that an advertised discount percentage matches the actual price difference ā retailers occasionally inflate the "original" price to make a discount look larger than it is.
Retail Psychology
Retailers sometimes set an inflated "original" price specifically to make a discount look larger, a practice regulators in several countries now restrict by requiring the "original" price to reflect a genuine price the item was actually sold at for a meaningful period beforehand. Using this calculator's reverse mode to check whether the claimed discount percentage matches the price difference can reveal inflated reference prices.
Percentage-off framing ("50% off") also tends to feel like a bigger saving than the equivalent amount-off framing ("ā¬50 off a ā¬100 item") to most shoppers, even though they're identical ā retailers choose whichever framing makes the deal look more attractive for a given price point.
Related Calculators
For related calculations, see our percentage calculator, VAT calculator, and currency converter.
Practical Use Cases
Shopping sales
Quickly checking the real price during seasonal sales or clearance events.
Stacked promotions
Verifying the true final price when a store applies multiple discount codes or promotions.
Verifying advertised savings
Checking whether an advertised discount percentage matches the actual price reduction.
Budgeting for purchases
Planning how much a discounted item will actually cost before checkout.
Reselling and pricing
Working out what original price a target sale price implies, when setting your own discounts.
Multiply the original price by the discount percentage to get the discount amount, then subtract it from the original price. For example: $100 with a 20% discount = $100 x 0.20 = $20 off, so the sale price is $80.
No. Stacked discounts are applied sequentially, not added. $100 with 30% off becomes $70, then an extra 20% off $70 is $14, giving a final price of $56 ā a 44% total discount, not 50%. Each discount applies to the already-reduced price.
Divide the sale price by (1 - discount% / 100). For example, if an item costs $80 after a 20% discount, the original price was $80 / 0.80 = $100.
Some retailers apply discounts to a different base (like a manufacturer's suggested price rather than the shelf price), round differently, or apply taxes before or after the discount. Always check the receipt breakdown if the numbers don't match exactly.
This calculator is designed for discounts (price reductions). For markups (price increases), use the percentage calculator instead, which handles both increases and decreases.
Use this calculator's reverse mode: enter the current sale price and the claimed discount percentage to see what the original price should have been. If that calculated original price doesn't match what the item was realistically selling for before the "sale," the discount may be based on an inflated reference price.
Mathematically, yes ā both result in the same ā¬50 discount and ā¬50 final price. However, percentage-off framing often feels like a bigger saving to shoppers than the equivalent amount-off framing, which is why retailers choose whichever framing makes a given deal look more attractive.