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Discount stacking calculator
Enter the price, the sale, your coupon code and your cashback rate. See what you really pay, in the order checkout applies them.
You really pay
$64.60
35.4% off the $100.00 price
Adding the three rates gives 40%. The real figure is lower because the code and the cashback each come off a price that’s already been cut.
- Price$100.00
- Sale, 20% off−$20.00
- Code, 15% off the sale price−$12.00
- You pay at checkout$68.00
- Cashback, 5% of that, paid later−$3.40
- Real cost$64.60
How it works
after sale = price × (1 − sale %)
you pay = after sale × (1 − code %)
(a $ code: after sale − code)
cashback = you pay × cashback %
real cost = you pay − cashback
discount = 1 − real cost ÷ price
Why you can’t just add them. A 20% sale and a 15% code are not 35% off. The code comes off the sale price, so you pay 80% × 85% = 68% of the price, which is 32% off. Cashback works the same way: it’s a share of what you paid, not of the original price.
When the order matters. Two percentage discounts give the same result in either order. A dollar code doesn’t: on a $100 item, $10 off and then 20% off leaves $72, while 20% off and then $10 off leaves $70. The store decides the order. This calculator takes the code off the sale price.
What cashback is paid on. Cashback is usually worked out on what you pay after discounts, without tax or shipping, and it arrives after the store approves the order. So it lowers your real cost, not the total at checkout. Each store’s terms say exactly what counts.
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Tenmomo. "Discount stacking calculator." https://tenmomo.com/tools/discount-stacking-calculator
<a href="https://tenmomo.com/tools/discount-stacking-calculator">Discount stacking calculator</a> by Tenmomo
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