CalcKitDiscount Calculator
Your discount
Example: $80 at 25% off → you save $20.00 and pay $60.00. Stacked: $100 at 20% then 10% off → you pay $72.00.
Behind the numbers
How a discount is calculated
A discount is a percentage of the original price. Multiply the price by the percentage to find what you save, then subtract it from the original price to find what you pay. When two discounts stack, the second one applies to the already-discounted price, not the original.
$80 at 25% off: $80 × 25 ÷ 100 = $20.00 saved, so you pay $80.00 − $20.00 = $60.00. Stacked: $100 at 20% then 10%: $100 × 0.80 × 0.90 = $72.00, which is 28% off in total, not 30%.
Three ways to use this calculator
In reverse mode, the discount is (price before − price after) ÷ price before × 100. A drop from $120 to $90 is a 25% discount.
A few comparisons
Example discounts
| Deal | You save | You pay | Effective discount |
|---|---|---|---|
| $80 at 25% off | $20.00 | $60.00 | 25% |
| $100 at 20% then 10% off | $28.00 | $72.00 | 28% |
| $250 at 40% off | $100.00 | $150.00 | 40% |
| $120 down to $90 | $30.00 | $90.00 | 25% |
Small discount. Real savings.
Stacked discounts never add up: 20% then 10% is 28% off, not 30%, because the second discount applies to the price after the first one.
Compare the final price, not the headline percentage. A 30% discount on a $200 item ($140) can still cost more than a 20% discount on a $150 item ($120).
Use reverse mode at the store: if a $120 jacket is marked down to $90, that is a 25% discount, so you can check whether a better coupon beats it.
Remember sales tax is usually charged on the discounted price, so the register total will be a little higher than the sale price shown here.
Good to know
Your questions, answered.
How do you calculate a discount?
Multiply the original price by the discount percentage to find what you save, then subtract it. For $80 at 25% off: $80 x 25 / 100 = $20.00 saved, so you pay $80.00 - $20.00 = $60.00.
Is 20% then 10% the same as 30% off?
No. Stacked discounts multiply: $100 at 20% off is $80, then 10% off $80 is $72, so you save $28 in total - a 28% discount, not 30%.
How do I find the original price from a sale price?
Divide the sale price by (1 - discount / 100). If you paid $60 after a 25% discount, the original price was $60 / 0.75 = $80.00.
How do I work out the discount percentage from two prices?
Subtract the sale price from the original price, divide by the original price and multiply by 100. A drop from $120 to $90 is ($120 - $90) / $120 x 100 = 25% off.