How this is calculated

A discount is a percent of the original price, subtracted from that price. Finding the original from a sale price is reverse percentage with a decrease.

sale = original × (1 − discount / 100)

  1. 15% of 200 is 30, so the sale price is 200 − 30 = 170.
  2. From original 80 and sale 68, the discount is (80 − 68) / 80 × 100 = 15%.
  3. From sale 170 and 15% off, the original is 170 / 0.85 = 200.

This uses the percent-of formula for the savings, then subtracts. It is not markup, which divides extra amount by cost.

Not the same as

A discount is percent off a selling price. These tools measure different gaps.

Discount questions

170. You save 30.

15%. (80 − 68) / 80 × 100 = 15.

200. Divide 170 by 0.85.

Yes, when the original price is the starting value. Percentage change reports that decrease without a savings line.

Open percentage change

Discount cuts a price. Markup adds to cost. Cost 100 to price 150 is markup, not a discount.

Open the markup calculator

100% off makes the sale price 0. Recovering an original from 100% off is not possible, because the factor would be zero.