Discount Calculator
What "30% Off" Actually Costs You
A percentage discount is easy to compute forward but easy to misjudge in reverse. Retailers sometimes advertise the discount rather than the final price, leaving shoppers to do the subtraction mentally — and stacking multiple discounts (a sale price plus a coupon) doesn't work the way most people assume, since each successive discount applies to an already-reduced price, not the original.
The Formula
Final Price = Price − Discount
Reverse: Original Price = Final Price ÷ (1 − Discount % ÷ 100)
The reverse mode solves for the original price when you only know the sale price and the discount percentage — useful for checking whether an advertised discount was actually applied correctly.
Where This Applies
- Retail and online shopping — comparing the real dollar savings across items with different discount percentages.
- Verifying a receipt — using the reverse mode to check that a listed discount matches the difference between original and sale price.
- Budgeting for a sale — figuring out the actual out-of-pocket cost before checkout, not just the percentage off.
$120 Item at Common Discount Levels
| Discount | Amount Off | Final Price |
|---|---|---|
| 10% | $12.00 | $108.00 |
| 20% | $24.00 | $96.00 |
| 30% | $36.00 | $84.00 |
| 50% | $60.00 | $60.00 |
Stacked discounts multiply rather than add: 20% off followed by a further 10% off is a combined 28% off the original price, not 30%.
How to Use This Calculator
- Choose the mode: Calculate Discounted Price or Find Original Price.
- Enter the Original Price or Final Price, depending on the mode.
- Enter the Discount percentage.
- Select Calculate to see the final price and discount amount, or the reconstructed original price.
Related Calculations
To add sales tax on top of a discounted price, see the Sales Tax Calculator, or calculate a service tip with the Tip Calculator.