English
العربية
Deutsch
Español
Français
Italiano
Português
Русский
Türkçe
Tiếng Việt
Discount Calculator
Work out the sale price and exactly how much you are saving.
The sign says 35% off. Your brain says “about a third”. Your brain is close enough for deciding whether to walk into the shop and not close enough for deciding whether it is actually a good deal.
Working out a discount
- Enter the original price.
- Enter the discount percentage.
- Read off the amount you save and the price you will actually pay.
- Change either number to compare offers side by side.
- Add tax afterwards if your local prices are quoted before tax.
The arithmetic, if you want to do it in your head
Multiply the price by the percentage and divide by 100 to get the saving, then subtract. So 35% off 80 is 80 × 35 ÷ 100 = 28 off, leaving 52.
The faster mental shortcut is to work with what you pay rather than what you save. 35% off means you pay 65%, so 80 × 0.65 = 52 in one step. Once that clicks you can do most shop-floor discounts without a calculator at all.
Quick reference
| Discount | You pay | On a price of 60 |
|---|---|---|
| 10% off | 90% | 54.00 |
| 20% off | 80% | 48.00 |
| 25% off | 75% | 45.00 |
| 33% off | 67% | 40.20 |
| 50% off | 50% | 30.00 |
| 70% off | 30% | 18.00 |
Stacked discounts do not add up
This is where shops quietly win. An extra 20% off an item already reduced by 30% is not 50% off. The second discount applies to the already-reduced price: 100 becomes 70, and 20% off 70 is 56 — a 44% total reduction, not 50%.
The same trap works in reverse with price rises. A 20% increase followed by a 20% decrease leaves you below where you started, because the decrease is calculated on the larger number.
Discount questions
How do I calculate a percentage discount?
Multiply the original price by the discount percentage, then divide by 100 to get the saving. Subtract that from the original price. Or go straight to the answer by multiplying by (100 − discount) ÷ 100.
How do I work out the original price from a sale price?
Divide the sale price by (100 − discount) ÷ 100. If an item is 45 after 25% off, the original was 45 ÷ 0.75 = 60. Adding 25% back to 45 gives the wrong answer.
What does 30% plus an extra 20% off really mean?
A total of 44% off, not 50%. The second discount is applied to the already-discounted price, so the two percentages compound rather than add.
Should I add sales tax before or after the discount?
After. The discount is applied to the pre-tax price, and tax is then calculated on the reduced amount. That is the standard order almost everywhere.
What discount takes a price to a specific target?
Divide the target by the original, subtract from 1 and multiply by 100. To get from 80 down to 60: 1 − (60 ÷ 80) = 0.25, so you need 25% off.
