Money
Discount Calculator
Enter the original price and the discount to see the sale price and the saving.
The link carries your figures, so it reopens on exactly these numbers.
What stacked discounts are really worth
“An extra 20% off” never adds to the first discount — it applies to the already-reduced price. Each row below is the equivalent single discount on your price.
| Offer | You pay | You save | Share of the original price |
|---|---|---|---|
| 30% off | $174.99 | $75 | 70% |
| 30% then an extra 20%Equivalent to 44% off, not 50%. 0.70 × 0.80 = 0.56. | $139.99 | $110 | 56% |
| 50% offWhat the two above are mistaken for. | $125 | $125 | 50% |
| 50% then an extra 20%Equivalent to 60% off, not 70%. 0.50 × 0.80 = 0.40. | $100 | $149.99 | 40% |
| Buy one, get one half priceTwo items for 1.5 times the price is 25% off each, not 50%. | $187.49 | $62.5 | 75% |
The formula
saving = price × discount ÷ 100
sale price = price − saving
Worked example
A $249.99 tool at 25% off
- 249.99 × 0.25 = 62.50 saved
- 249.99 − 62.50 = 187.49 to pay
Where this goes wrong
Adding stacked discounts together
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, then $56 — a real saving of 44%. Stacked percentages multiply, and they always come out smaller than their sum.
Questions
- How do I apply two discounts one after the other?
- Apply them in sequence, not by adding them. 20% off then 10% off is not 30% off: it leaves you paying 0.8 × 0.9 = 0.72, so 28% off. Run this calculator twice, using the first result as the second price.
- Does the discount apply before or after sales tax?
- In the United States, the discount is applied first and sales tax is charged on the reduced price. Enter the pre-tax price here, then add tax to the result.
- How do I find the original price from the sale price?
- Divide the sale price by 1 minus the discount as a decimal. A $187.49 item after 25% off started at 187.49 ÷ 0.75 = $249.99.