Discount Calculator
How much will it cost, and how much do you really save? Enter the original price and the discount as a percentage or an amount to get the sale price and your saving. Add an extra discount to see why “25% plus 10% off” is not 35%, add sales tax, or switch modes to find the discount percentage from an original and a sale price.
- Runs in your browser
- No sign-up
- Free to use
For “an extra 10% off sale prices”. Applied after the first discount.
How to use Discount Calculator
- Choose whether to calculate the sale price or the discount percentage.
- Enter the original price and the discount, or the sale price.
- Add an extra discount and sales tax if they apply.
- Read the price, the saving and the working.
Discount Calculator features
Percent or amount
Discounts as a percentage or a fixed amount off.
Stacked discounts
Applies an extra discount to the reduced price and shows the true combined rate.
Reverse mode
Finds the discount percentage from two prices.
Tax on top
Adds sales tax or VAT to the discounted price.
Any currency
Formats amounts in your currency.
Shows the working
The formula is printed under the result.
When to use Discount Calculator
- Checking a sale price in a shop or online.
- Comparing two offers.
- Pricing a promotion for your own products.
- Working out the real discount of a “was/now” price.
Discount Calculator FAQ
How do I calculate a percentage discount?
Multiply the price by the percentage and subtract: 25% off 80 is 80 × 0.25 = 20, so the sale price is 60.
Is 25% off plus 10% off the same as 35% off?
No. The second discount applies to the already reduced price: 80 → 60 → 54, a combined discount of 32.5%, not 35%.
How do I find the discount percentage from two prices?
Divide the difference by the original price: (80 − 60) ÷ 80 = 25%.
Is tax calculated before or after the discount?
Usually after: sales tax or VAT is charged on the price actually paid. The calculator adds tax to the discounted price.
What if the sale price is higher than the original?
The reverse mode shows it as a price increase.
Is the “original price” always genuine?
Not always. Some retailers inflate reference prices. Compare with prices elsewhere before deciding a discount is real.
Percentages that do not add up
Discounts look simple, and a single percentage off a single price is. The traps appear when discounts are combined, when tax is involved, or when a discount is quoted as an amount rather than a rate. This calculator handles those cases and shows the arithmetic.
Stacked discounts are the classic confusion. “An extra 10% off sale prices” applies to the already reduced price, so it is worth less than 10% of the original. Two discounts of 25% and 10% combine to 32.5%, not 35%. The order does not matter for the final price, but adding the percentages always overstates the saving.
Tax is normally charged on the price after discount, so a discount also reduces the tax you pay. Fixed-amount discounts behave differently from percentages: £10 off is a large share of a cheap item and a small share of an expensive one. Converting both into a percentage makes offers comparable.
Finally, a discount is only as good as its reference price. Consumer protection rules in many countries require that a “was” price was genuinely charged, but practice varies. When the saving matters, compare the sale price with what the product costs elsewhere.