Discount Stacking Calculator
Several discounts on one price — see what you’ll really pay.
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The price
Before anything is taken off.
Discounts, in the order they are applied
Tax and shipping
Checked against the price after discounts, as most shops do.
The usual case, and what store coupons normally do.
Enter a list price to see what the stack comes to.
Step by step
| Step | Price before | Takes off | Price after |
|---|---|---|---|
| Shipping | $0.00 | ||
| Tax | $0.00 | ||
| You pay | $0.00 | ||
Your files stay on your device
How to use it
Enter a price and each discount in order to see what you’ll really pay. 20% off then 10% off is 28% off, not 30%.
Sale price, plus a member discount, plus a coupon? Enter the price and each offer, and see what you’ll actually pay — plus what it all adds up to as a single discount.
Discounts don’t simply add up. 20% off and then 10% off is 28% off, not 30%, because the second discount is taken from the already-lower price. Three 20% discounts come to 48.8%, not 60%.
Order matters for money-off coupons. A $20 coupon is worth the full $20 after a percentage discount, but less before it. The tool shows the best order — handy to know at the checkout.
Add tax and a free-shipping threshold to see the true total. Sometimes a bigger discount drops you under free shipping and costs you more!
FAQ
Is 20% off plus 10% off the same as 30% off?
No — it’s 28% off, because the second discount comes off the already-reduced price.
Does the order of discounts change the price?
Only for money-off coupons. A $20 coupon is worth more after a percentage discount than before it.
How do I work out stacked discounts?
Take each discount off the new price, not the original. The tool shows the price after every step.
Is tax charged before or after a discount?
Usually after, on the lower price. Some places tax the full price for manufacturer coupons, so there’s a switch.
What if a coupon is worth more than the item?
Only part of it can be used — the rest isn’t refunded. The tool tells you when this happens.
How it worksFor the curious
Discounts run sequentially on the running price rather than adding rates: 20% then 10% leaves 80% × 90% = 72% of list. The equivalent single percentage is shown with the result.
Percentages commute among themselves, but a fixed coupon applied before a percentage loses that percentage of its value. The tool compares your order with the best possible order; retailers often specify their own order in their terms.
Tax applies to the discounted price by default; some US states tax the pre-coupon price on manufacturer coupons, so there is a switch. Free-shipping thresholds are measured against the discounted subtotal. A coupon cannot take a price below zero, and leftover value is reported rather than counted as a saving.