Everyday math · Shopping
Check the sale price before checkout.
Stack a discount and an extra percentage, add sales tax, and see exactly what you save.
Price and discounts
Stack an extra percentage off, then add tax if needed.
Final price
$90.00
You save
$30.00
Effective discount
25%
Discounted subtotal
$90.00
Tax
$0.00
A second percentage is applied to the already-discounted price, not added to the first discount. Taxes and exclusions vary by location.
Good to know
The result is a guide, not a guarantee.
This calculator runs entirely in your browser. Check the assumptions, keep the inputs realistic, and use the result as a starting point for a decision.
Retail estimate. Tax rules, exclusions and shipping vary by location and seller.
How do stacked discounts work?
The second percentage is applied to the already-discounted price. An extra 10% off an item already reduced by 20% is not a 30% discount; it is 28% off the original price.
When is sales tax added?
Tax is calculated on the discounted subtotal, which is the usual retail convention. Some jurisdictions tax the original price or exclude certain items, so check the receipt.
What is the effective discount?
It is the total saving as a percentage of the original price, after all discounts but before tax. It makes stacked offers easier to compare.
Does the calculator include coupons or shipping?
No. Enter coupon percentages in the discount fields. Shipping, handling and return fees are separate and can change the real cost.