Double Discount / Stacked Sale Calculator
Two sequential discounts stack multiplicatively, not additively.
Final price
$59.50
Total savings
$40.50
Effective discount
40.5%
Discounts stack multiplicatively, not additively
It's tempting to add 30% + 15% and assume 45.0% off — but the second discount applies to the already-discounted price, so the real combined discount is only 40.5% off.
What is this tool?
When a sale price gets a second discount on top (a coupon, a loyalty discount), the second percentage applies to the already-reduced price, not the original — so 30% off plus 15% off is not 45% off. This calculator shows the actual final price and combined effective discount, contrasted against the naive additive sum shoppers often assume.
How to use it
- Enter the original price.
- Enter both discount percentages, in either order.
- Compare the real effective discount against the naive additive sum.