What the Discount Calculator does
Sales, coupons and promo codes almost always give the discount as a percentage, but what you really want to know is the price you pay and how much money stays in your pocket. This discount calculator turns a price and a percentage into both numbers instantly, so you can compare offers in a shop, online or on a price tag without doing the maths in your head.
Many offers combine two discounts – for example 30% off everything plus an extra 10% for members, or a clearance price with an additional coupon. These discounts are not simply added together, because the second one is taken from the already reduced price. Enter both and the calculator shows the real total discount, along with a short note explaining the difference.
If you need the final amount at the checkout, add the sales tax or VAT rate as well. The tax is applied to the discounted price, just as it is on a real receipt. Everything runs in your browser, results update while you type, and nothing is stored or sent anywhere.
When to use it
Shopping and sales
See what 25%, 40% or 70% off really means for the price on the tag before you go to the till.
Coupons and promo codes
Combine a sale price with an extra coupon and find out the real total discount.
Comparing offers
Is “£20 off” or “15% off” the better deal? Calculate both and compare the final prices.
Pricing your own products
Shop owners can check the sale price and the margin they give away before starting a promotion.
Tips for the best results
- Two discounts never add up to their sum: 50% + 50% off is 75% off, not free.
- For a fixed amount off, such as £15 off £60, divide the amount by the price to get the percentage: 15 / 60 = 25%.
- A price that is first raised by 20% and then cut by 20% ends up 4% lower than the original, not unchanged.
- Check whether a coupon applies before or after other discounts – the order does not change the result for percentages, but it does for fixed amounts.
How the Discount Calculator works
The sale price is calculated as price × (1 − discount / 100). With 25% off £80 that is 80 × 0.75 = £60, and the amount saved is the difference, £20.
A second discount is applied to the result of the first: price × (1 − d1 / 100) × (1 − d2 / 100). The total discount is then 1 minus the product of both factors, which is why 20% and 10% give 1 − 0.8 × 0.9 = 28%.
If you enter a tax rate, the calculator multiplies the discounted price by (1 + tax / 100). All amounts are shown with two decimals and formatted for your region.