How to use the Discount Calculator tool
- Choose what you want to knowThe sale price, the original price before a discount, or the discount percentage.
- Enter the prices and discountType the original or sale price and the discount percentage.
- Add extras (optional)Enter a second discount, such as an extra coupon, and a sales tax or VAT rate.
- Read the resultSee the price, your savings and the true total discount instantly.
Features
- Sale price & savingsThe quickest way to check a “25% off” label in a shop or online.
- Stacked discountsCombine a sale with a coupon and see the real total discount.
- Original priceFind out what an item cost before the discount.
- Discount percentageCompare two prices and see the percentage saved.
- Tax includedAdd sales tax or VAT to get the final checkout price.
How to calculate a discount
Sale price = Original price × (1 − Discount ÷ 100)
Example: an item costing 80 with 25% off: 80 × 0.75 = 60. You save 20.
A quick mental shortcut: to find 25% of 80, take 10% (8), double it (16) and add half of 10% (4) to get 20.
Stacked discounts don’t add up
Shops often advertise “an extra 20% off sale prices”. It is tempting to add the two discounts together, but they are applied one after the other, so the second discount is taken from an already reduced price:
- Original price 100, first discount 25% → 75
- Extra 20% off 75 → 60
The total discount is 40%, not 45%. Use the “Extra discount” box to see the true combined figure.
Finding the original price
If you know the sale price and the discount, divide instead of adding the percentage back:
Original price = Sale price ÷ (1 − Discount ÷ 100)
Example: a sale price of 60 after 25% off came from 60 ÷ 0.75 = 80. Adding 25% to 60 would wrongly give 75.
Calculating the discount percentage
Discount % = (Original − Sale) ÷ Original × 100
Example: a price drop from 80 to 60 is (80 − 60) ÷ 80 × 100 = 25%. This is useful for checking whether a “sale” is really a bargain, or for comparing offers in different shops.
Discounts and sales tax
In most countries, sales tax or VAT is charged on the discounted price, not the original price. In the US, prices are usually shown before tax, so enter your state or local sales tax rate to see what you will pay at checkout. In the UK, EU, India and many other countries, displayed retail prices already include VAT or GST, so leave the tax field at 0.
To work with tax on its own, try our GST / VAT Calculator.