How to calculate a discount

Calculate the discount amount

Multiply the original price by the percentage written as a decimal:

discount amount = original price x discount / 100

For a $1,200 item discounted by 25%:

1200 x 25 / 100 = 300

The discount is $300. See how to calculate percentages if you want to review the underlying operation.

Calculate the final price

Subtract the discount from the original price:

1200 - 300 = 900

The sale price is $900. Equivalently, multiply the original price by the percentage that remains: 1200 x 0.75 = 900.

Be careful with stacked discounts

Successive discounts are not added directly. On a $1,000 item, 20% off followed by an additional 10% gives:

1000 x 0.80 = 800
800 x 0.90 = 720

The effective discount is 28%, not 30%, because the second discount applies to the already reduced price. The full method is explained in successive discounts.

Compare the final amount payable

The headline percentage is only one part of a purchase. Include shipping, taxes, financing charges and eligibility restrictions before comparing offers. Use the percentage calculator to check both the discount and final price.