How to use the discount calculator
- Enter the original price before any discount.
- Choose percent off or amount off, then enter the discount.
- To stack a coupon or extra markdown on top, tick add a second discount and enter it the same way. It comes off the price after the first discount.
- Optionally enter your sales tax rate. It is added to the discounted price.
- Read the final price, what you save, and the effective total discount.
How the discount is calculated
A second percentage discount is taken from the price that is left after the first one, not from the original price. That is why two stacked discounts are always worth a little less than their sum. Sales tax is worked out on the discounted price, since that is what most stores charge tax on for their own markdowns.
Worked example
The calculator starts with an $80 item at 25% off, with no second discount and no sales tax:
- Discount: $80 × 25 ÷ 100 = $20
- Final price: $80 − $20 = $60.00
- You save $20, a 25% total discount
Now tick the second discount, which defaults to an extra 10% off. It comes off the $60, not the $80: $60 × 10% = $6, so the price drops to $54.00. Your total saving is $26, which is $26 ÷ $80 = 32.5% of the original price, not 35%.
If the first discount were $15 off instead, the price would be $80 − $15 = $65.00. And with 8% sales tax on the original 25% deal, you would pay $60 × 1.08 = $64.80 at the register.
What stacked discounts are really worth
| First discount | Second discount | Looks like | Actually |
|---|---|---|---|
| 20% | 10% | 30% | 28% |
| 25% | 10% | 35% | 32.5% |
| 30% | 20% | 50% | 44% |
| 40% | 25% | 65% | 55% |
| 50% | 50% | 100% | 75% |
To combine two percentage discounts yourself, multiply what you keep: 0.75 × 0.90 = 0.675, so you pay 67.5% of the price and save 32.5%. The order doesn't matter when both are percentages. It does matter when one is a dollar amount: $10 off then 20% off $80 gives $56, while 20% off then $10 off gives $54. Stores decide the order, so read the coupon terms.
Before you buy
A discount is only as good as the starting price. Compare the sale price with what other sellers charge, not with the "was" price on the tag. For quick single markdowns with tax, and a table of prices from 10% to 75% off, try the percent off calculator. If you sell the item yourself, check what a discount does to your profit with the margin calculator.
Frequently asked questions
How do I calculate a discount in my head?
Find 10% by moving the decimal point one place to the left, then scale it. For 30% off $80, 10% is $8, so 30% is $24 and the sale price is $56. For 25% off, divide the price by 4.
Is 20% off plus 10% off the same as 30% off?
No. The 10% comes off the already reduced price, so together they take 28% off, not 30%. On a $100 item that is $72 instead of $70.
Is sales tax charged before or after a discount?
For a store's own discount, tax is normally charged on the reduced price, and that is what this calculator does. Manufacturer coupons can be treated differently, and the rules vary by state, so your receipt may show tax on a higher amount.
How do I find the original price from a sale price?
Divide the sale price by 1 minus the discount as a decimal. A $60 price after 25% off came from $60 ÷ 0.75 = $80.
Related calculators
- Percent Off Calculator — Quick sale price for any percent off, the amount you save, and the total with sales tax.
- Sales Tax Calculator — Add sales tax to a price, take it back out of a total, or find the rate from a receipt.
- Margin Calculator — Gross profit, margin and markup from cost and price, or the selling price you need for a target margin or markup.
- Percentage Calculator — Percent of a number, what percent one number is of another, percentage change and difference.
Results are estimates for educational purposes and are not financial, tax or legal advice. See our disclaimer.