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How to Calculate a Discount and Sale Price

A 25% discount sounds simple, but it is easy to mix up the saving with the price you pay. A short calculation shows both, and tells you the total once tax is added.

The two numbers you need

The saving is the original price multiplied by the discount percentage, divided by 100. The sale price is the original price minus that saving. For an 80 item with 25% off, the saving is 20 and the sale price is 60.

A quick check

A discount of 50% always halves the price, and a discount of 10% takes one tenth off. If your answer does not match these shortcuts, recheck the arithmetic.

Discounts and tax

In most places, sales tax is added to the discounted price, not the original one. For example, a sale price of 60 with 8% tax costs 64.80 in total. Check the rules where you live, because some places handle it differently.

Stacked discounts

Two discounts applied one after the other do not add together. Take 20% off, then 10% off the new price. A 100 item becomes 80, then 72. That is a total discount of 28%, not 30%.

Try it yourself

The Discount Calculator shows the sale price, the saving and the total with tax as you type.