Discount Calculator
Find the sale price and how much you save from any percentage discount.
Results update as you type.
About this calculator
A discount calculator applies a percentage off an original price to give you the final sale price and the amount you save. The saving is the price multiplied by the discount percent and divided by 100; the sale price is what is left after subtracting it. Add a second discount or a tax rate under advanced options to see the true checkout price.
For example, 25% off an 80 item saves 80 × 25 ÷ 100 = 20, so the sale price is 60. If a second 10% coupon applies, it comes off the already-reduced 60 — not the original — giving 60 × 0.90 = 54. That is why stacked discounts are always worth less than simply adding the two percentages together.
Use it while shopping to check whether a "40% off" tag is really the best deal, to compare two offers, or to work out the final price when a store code stacks on a sale. Turn on the tax field to see the actual amount you will hand over at the register.
Frequently asked questions
How do I calculate a percentage discount?
Multiply the price by the discount percent and divide by 100 to get the saving, then subtract it. 25% off 80 is a saving of 20, so the final price is 60.
How do stacked discounts work?
A second discount applies to the already-reduced price, not the original. 25% off then 10% off 80 gives 80 → 60 → 54, not 52.
How do I calculate the final price after a discount?
Multiply the original price by (1 − discount ÷ 100). For 25% off 80: 80 × 0.75 = 60. The amount you save is the original minus that figure — here 20.
Is 50% off then 20% off the same as 70% off?
No. The 20% comes off the price already reduced by 50%, so 100 → 50 → 40, an effective 60% off — not 70%. Stacked percentages never simply add together.
How do I find the original price from a sale price?
Divide the sale price by (1 − discount ÷ 100). If an item is 60 after 25% off, the original was 60 ÷ 0.75 = 80. This reverses a single discount.
How do I add sales tax to a discounted price?
Work out the sale price first, then multiply by (1 + tax ÷ 100). The tax field under advanced options does this automatically, so the final figure is what you actually pay at checkout.
API — use this calculator from code
Call this calculator as a free JSON endpoint — no key required. Send the field values below as query parameters or JSON. Read the full API docs →
Endpoint
GET https://calculator.free/api/v1/discount/curl
curl "https://calculator.free/api/v1/discount/?price=80&percent=25"JavaScript fetch()
const r = await fetch(
"https://calculator.free/api/v1/discount/?" + new URLSearchParams({
"price": "80",
"percent": "25"
}));
const data = await r.json();
console.log(data.results);Results are estimates for general guidance only, not financial, medical or tax advice.