Discount Calculator
Single Discount
Stacked Discounts
Show the math
What Your Result Means
- Final price: The amount you pay after the discount is applied. For stacked discounts, this reflects both discounts applied sequentially, not added together.
- You save: The dollar amount taken off the original price. Use this to compare deals across different stores or discount structures.
- Stacked discounts are not additive: A 20% off followed by 10% off is not the same as 30% off. The second discount applies to the already-reduced price, so the combined savings are slightly less than the sum of the two percentages.
How This Calculator Works
You enter the original price and one or two discount percentages. For a single discount, the tool multiplies the price by the discount rate to get the savings, then subtracts that from the original price. For stacked discounts, it applies the first discount to the original price to get an intermediate price, then applies the second discount to that intermediate price. The order of stacked discounts does not affect the final result — 20% then 10% gives the same final price as 10% then 20%.
Quick Questions
Does the order of stacked discounts matter?
No. Mathematically, multiplying by (1 − d1) × (1 − d2) gives the same result regardless of order. A 20% off then 10% off equals a 10% off then 20% off. The final price and total savings are identical either way.
How do I calculate the effective total discount from stacked percentages?
Multiply (1 − first discount) × (1 − second discount), then subtract from 1. For example, 20% and 10% stacked: (1 − 0.20) × (1 − 0.10) = 0.72, so the effective discount is 28%, not 30%.
Should I apply a coupon before or after a store sale?
Mathematically it does not matter — the final price is the same. However, some stores apply their sale first and then the coupon on the reduced price. Check the store's coupon policy to confirm they honor stacking.
Does this include sales tax?
No. Sales tax is typically calculated on the discounted price, not the original. To estimate your total out-of-pocket cost, take the final price from this calculator and add your local sales tax rate. Try the sales tax calculator for a quick estimate.
Sources
- FTC — Advertising FAQs (rules on advertised discounts and pricing)
- Wikipedia — Discount (general overview of discount mathematics)
Method & review
Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.