Find the original price
Find the discount amount or discount rate
If you have the discount amount, divide it by the original price
Multiply the result by 100
Percent off = (discount amount ÷ original price) × 100
If you have the sale price, subtract it from the original price to get the discount amount
Then use the same formula
Percent off = ((original price – sale price) ÷ original price) × 100