Discount Calculator
Find out what you'll actually pay after a discount. Enter the original price and the discount percentage to get the final price and the amount saved. You can also stack a second discount (say, 20% off plus an extra 10% off) — the tool applies them sequentially, the way stores do, which is less than adding the percentages together.
Calculators
Private by default
This tool runs entirely in your browser. Your data is never uploaded to a server.
How it works
How the sale price is calculated
Sale price = original price × (1 − discount ÷ 100)
The discount is a share of the original price, and what you pay is what's left of it. A second, stacked discount is applied to that result rather than to the original price — which is exactly why two discounts never add up to their sum.
- Stacked discounts multiply: 20% then 10% leaves you paying 0.80 × 0.90 = 72% of the original, so the real total is 28% off.
- The order doesn't matter. 20% then 10% and 10% then 20% both land on 72%.
- Nothing is rounded between the two steps; only the displayed prices are rounded to cents.
- Sales tax is not included. Tax is normally charged on the discounted price, so apply the discount first.
For reference
Common discounts at a glance
What each discount leaves you paying, on a $50 item and a $120 one.
| Discount | You pay | $50 becomes | $120 becomes |
|---|---|---|---|
| 10% off | 90% | $45.00 | $108.00 |
| 15% off | 85% | $42.50 | $102.00 |
| 20% off | 80% | $40.00 | $96.00 |
| 25% off | 75% | $37.50 | $90.00 |
| 30% off | 70% | $35.00 | $84.00 |
| 40% off | 60% | $30.00 | $72.00 |
| 50% off | 50% | $25.00 | $60.00 |
| 70% off | 30% | $15.00 | $36.00 |
| 20% then 10% | 72% | $36.00 | $86.40 |
| 30% then 20% | 56% | $28.00 | $67.20 |
| 50% then 20% | 40% | $20.00 | $48.00 |
The last three rows are stacked discounts — a storewide sale plus a coupon at the till, which is how most double discounts actually happen.
How to use
4 clear steps.
Enter the original price.
Enter the discount percentage.
Optionally add a second, stacked discount.
Read the final price and total savings.
Good to know
Frequently asked questions
- How do I calculate 20% off a price?
- Multiply the price by 0.20 to get the discount, then subtract it. For $45: 45 × 0.20 = $9 off, so you pay $36. Equivalently, multiply the price by 0.80.
- Is 20% off plus 10% off the same as 30% off?
- No. Stacked discounts apply one after the other: 20% then 10% leaves you paying 80% × 90% = 72% of the original — a 28% total discount, not 30%.