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Discount calculator
This discount calculator shows the sale price and how much you save. Enter the original price and the percent off. Add a second or third discount and sales tax if you need them. The answer updates as you type.
Loading the discount calculator.
How to use the discount calculator
- Original price. Type the price before any discount. Use your own currency. The tool only works with the numbers.
- Percent off. Type the percentage discount, or tap one of the common ones.
- Second and third discount. Optional. Use these for a double discount or a triple discount, such as a sale price plus a coupon plus a member offer.
- Sales tax. Optional. Type the tax rate to see the discount with tax added.
The big number is the final price you pay. Under it you see the amount saved, the total percent saved, the price before tax and the tax amount.
Want to do it without a calculator? Read the guide: how to calculate a discount, with shortcuts you can do in your head.
Percent off formula
A percentage discount removes a share of the price. What is left is the sale price.
Sale price = Original price × (1 − Percent off ÷ 100)
Each extra discount is taken off the price that is left, not off the original price. Tax is added at the end.
Final price = Original price × (1 − D1 ÷ 100) × (1 − D2 ÷ 100) × (1 − D3 ÷ 100) × (1 + Tax ÷ 100)
Worked example
A jacket has an original price of 80. It is 25% off, you have a coupon for an extra 10% off, and sales tax is 8%.
- First discount: 80 × 0.75 = 60.
- Second discount: 60 × 0.90 = 54. This is the price before tax.
- Tax: 54 × 0.08 = 4.32.
- Final price: 54 + 4.32 = 58.32.
You save 80 − 54 = 26 before tax. That is 26 ÷ 80 = 32.5% off in total, not 35%.
Why 20% then 10% off is not 30% off
Stacked discounts do not add up. The second discount applies to a price that is already lower, so it takes off less.
Take a price of 100. With 20% off it drops to 80. The extra 10% is 10% of 80, which is 8, not 10. You pay 72. That is 28% off in total, not 30%.
The table shows what common double discounts are really worth.
| First discount | Second discount | Looks like | Real percent off |
|---|---|---|---|
| 10% | 10% | 20% | 19% |
| 20% | 10% | 30% | 28% |
| 20% | 20% | 40% | 36% |
| 25% | 25% | 50% | 43.75% |
| 30% | 20% | 50% | 44% |
| 50% | 20% | 70% | 60% |
| 50% | 50% | 100% | 75% |
Practical notes
- Order does not matter. 20% then 10% gives the same price as 10% then 20%. Both leave you paying 72% of the original.
- Discount with tax. The tool adds tax to the price after the discounts, which is how most shop sales work. Rules differ by place and by type of coupon, so check your receipt if the numbers do not match.
- Fixed amounts off. For a coupon worth a set amount, subtract it from the original price yourself, then enter the result as the price.
- Rounding. Results are rounded to two decimal places. A shop may round each step, which can move the total by a cent.
Sale ending soon? Count the days left with the days between dates tool. For percentages at school, try the grade calculator or the final grade calculator.
How this calculator was checked
Built by Rasel Hakkani, WordPress developer at Swift Web Dev. The results were checked against hand-worked answers, including two and three discounts in a row, sales tax and 100% off.
Last checked: October 2026. Found a wrong answer? Tell us and we will fix it.
Discount calculator questions
How do I calculate a percentage discount?
Multiply the original price by the percent off, then divide by 100. That is the amount you save. Subtract it from the original price to get the sale price. For 20% off 100, you save 20 and pay 80.
Is 20% off plus 10% off the same as 30% off?
No. The second discount is taken off the reduced price. On a price of 100, 20% off leaves 80 and 10% off 80 leaves 72. That is 28% off in total, not 30%.
Does the order of the discounts matter?
No. Each discount multiplies the price by a fixed share, and multiplying in a different order gives the same answer. 20% then 10% and 10% then 20% both leave 72% of the original price.
Is sales tax worked out before or after the discount?
This calculator applies tax after the discounts, to the reduced price. That matches most shop sales. Some places tax certain coupons differently, so treat your receipt as the final word.
How do I find the original price from a sale price?
Divide the sale price by 1 minus the discount as a decimal. If you paid 60 after 25% off, the original price was 60 ÷ 0.75 = 80.
Which currency does the percent off calculator use?
Any. It shows plain numbers with two decimals and no currency symbol, so you can read the result in dollars, pounds, euros, taka or anything else.
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