How to Calculate a Discount and Sale Price

The basic formula

Saving = original price x (discount / 100). Final price = original - saving — or more directly, original x (1 - discount / 100). So an $80 jacket at 25% off is 80 x 0.75 = $60, saving $20.

Thinking in "what you pay" is often faster than "what you save": 25% off means you pay 75%. The Discount Calculator shows both the saving and the final price at once.

Mental shortcuts for the shop

Round to friendly percentages. 10% is the price with the decimal moved one place left; 5% is half of that; 20% is double the 10%. For 15% off a $40 item: 10% is $4, 5% is $2, so 15% is $6 off — you pay $34.

When in doubt, compute the amount you pay rather than the amount you save — it is one step instead of two, and it is the number at the till.

Stacked discounts do not add up

"30% off, then an extra 20% off" is not 50% off. Each discount applies to the price left after the previous one: $100 -> 30% off = $70 -> 20% off that = $56. That is a 44% total discount, not 50%. Multiply the factors instead: 0.70 x 0.80 = 0.56, so you pay 56%.

Discount first, then tax

In most places the discount comes off first and tax is charged on the reduced price. A $200 item at 15% off is $170; add 8% tax and you pay 170 x 1.08 = $183.60. Doing it in the other order gives a different, wrong total — so discount first, then tax.

Frequently asked questions

How do I find the original price from a sale price? Divide by (1 - discount / 100). A $60 item that was 25% off originally cost 60 / 0.75 = $80.

Is "buy one get one 50% off" the same as 25% off? Across the two items, yes — you pay for 1.5 items out of 2, which is 75% of the total, a 25% saving overall.

What does "up to 70% off" really mean? Only that at least one item reaches 70% off; most of the range is usually discounted far less.