How to use
- Pick a calculation at the top.
- Discount % → sale price: enter the original price and the discount to get the sale price and how much you save.
- Sale price → discount %: enter the original and sale prices to see the percent off.
- Stacked discounts: for an extra discount on top of a sale (a coupon, a loyalty code), get the final price and the true total discount.
- Thousands separators (1,250) are fine. Results update as you type.
- Use the Copy button on the result to grab the value.
Formulas
| Calculation | Formula | Example |
|---|---|---|
| Sale price | price × (1 − discount ÷ 100) | 25% off 80 = 60 |
| Amount saved | price × discount ÷ 100 | 25% of 80 = 20 |
| Percent off | (price − sale) ÷ price × 100 | 49.99 → 34.99 = about 30.01% |
| Stacked final price | price × (1 − a) × (1 − b) | 200 with 20% + 10% = 144 |
| Effective total discount | 1 − (1 − a) × (1 − b) | 20% + 10% = 28% |
Why 20% off plus an extra 10% is not 30%
The extra discount is taken from the already reduced price, not the original.
- 200 with 20% off → 160
- 160 with an extra 10% off → 144 (16 less)
- Total saved 56 ÷ original 200 = 28%
A true 30% discount would be 140, so the stacked deal costs 4 more. Two percentage discounts give the same final price in either order. But once a fixed-amount coupon (“$10 off”) is involved, order matters: subtracting the fixed amount first shrinks the base the percentage discount is applied to.
Things to watch
- Discounts must be between 0% and 100%. If the sale price is higher than the original, the tool reports the increase instead.
- Results show up to two decimal places. Stores round to the cent in their own way, so a checkout total can differ by a cent.
- Use the VAT calculator to add VAT or sales tax to the sale price, or the margin calculator to see what a discount does to a seller’s profit.
FAQ
How do I find the original price from the sale price?
Divide the sale price by (1 − discount ÷ 100). If 20% off leaves 160, the original was 160 ÷ 0.8 = 200. The percentage calculator helps with related checks.
Is “40% off” the same as “pay 60%”?
Yes. 40% off means you pay 60% of the original price — 30 for an item listed at 50.