Discount Calculator
Use this discount calculator to find the sale price of anything marked down by a percentage. Enter the original price and the discount, add an extra percent off if the store is stacking deals, and optionally include your sales tax rate. You'll see the final price, how much you save, the true combined discount and the tax charged on the discounted amount.
Updated
Results
- You saveOriginal price minus discounted price, before tax
- Total discountAll discounts combined
- Sales taxCharged on the discounted price
Results are estimates. See the methodology below.
How to use the calculator
- Original price: the regular price before any discount, usually the one on the tag.
- Discount: the percentage off, such as 25 for “25% off”.
- Advanced options – additional discount: a second percentage applied after the first, for offers like “take an extra 20% off sale prices” or a coupon on top of a markdown. Leave it at 0 if there isn't one.
- Advanced options – sales tax rate: your state and local rate, if you want the price you'll actually pay at the register. Leave it at 0 to see the pre-tax price.
The sales tax line only appears when you enter a tax rate.
How discounts are calculated
Each discount multiplies the price that is left after the previous one:
Discounted price = Price × (1 − d₁) × (1 − d₂)
Here d₁ is the first discount and d₂ the additional one, both as decimals. That is why stacked discounts never simply add up. The combined discount is:
Total discount = 1 − (1 − d₁) × (1 − d₂)
With 20% plus 10%, that's 1 − 0.80 × 0.90 = 28%, not 30%. Sales tax is then charged on the discounted price, which is how most stores calculate it for their own markdowns:
Final price = Discounted price × (1 + tax rate)
Amounts are rounded to the cent. “You save” compares the original price with the discounted price before tax.
Examples
1. A simple markdown
A $120.00 item at 25% off costs $90.00; you save $30.00.
2. Stacked deals with sales tax
An $80.00 jacket is 30% off, and the store takes an extra 20% off sale prices. With an 8.25% sales tax rate, the final price is $48.50. The discounted price is $44.80, so you save $35.20, the combined discount is 44% (not 50%) and the tax is $3.70.
3. Why “50% + 50%” is not free
| Original | Discounts | You pay | Total discount |
|---|---|---|---|
| $100.00 | 20% + 10% | $72.00 | 28% |
| $100.00 | 50% + 50% | $25.00 | 75% |
The second discount always applies to a smaller amount, so its dollar value is smaller than the first.
Reading the result
The total discount is the single percentage that would give the same price as all the stacked offers. Use it to compare deals: “40% off” beats “30% plus an extra 10%”, which works out to 37%.
A big percentage is only a good deal if the original price is real. Under the Federal Trade Commission's Guides Against Deceptive Pricing, a former price used in a comparison should be one at which the item was openly and actively offered for a reasonably substantial period, not a price inflated just to make a markdown look bigger. Comparing the final price across stores is usually more useful than comparing percentages.
Frequently asked questions
How do I calculate a percentage off?
Multiply the price by (1 − discount ÷ 100). For 25% off $120.00, that's $120.00 × 0.75 = $90.00. The savings are the difference, $30.00.
Do two discounts add up?
No. The second discount applies to the already reduced price. 20% off followed by 10% off is a 28% total discount; 30% plus 20% is 44%.
Is sales tax charged before or after the discount?
For a store's own discount, sales tax is generally charged on the reduced price, which is what the calculator does. Rules for manufacturer coupons and rebates differ by state, so in those cases the taxable amount may be the price before the coupon. Your state revenue department publishes the exact rules.
Does the order of the discounts matter?
Not for percentages. Multiplication is commutative, so 30% then 20% gives the same price as 20% then 30%. Order only matters when you mix a percentage with a fixed dollar amount off.
How do I find the original price from the sale price?
Divide the sale price by (1 − discount). A $90.00 item that is 25% off was $90.00 ÷ 0.75 = $120.00 before the markdown.
Sources
Results are estimates for comparison only. The price you pay depends on the store's terms, coupon rules and the sales tax that applies where you buy.