Discount Calculator (Sale Price & Savings)
Work out the sale price and what you actually save, including stacked discounts, which do not simply add up.
- You pay
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- Original price
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- Real discount
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Free forever, no sign-up and no limits, and this tool installs on its own so you can keep it on your home screen.
Type the price and the percentage off to get the amount saved and the sale price. Add a second discount on top and the tool shows the real combined percentage, because 25% plus an extra 10% is 32.5% off, not 35%, and shops know most people add them. It also works backwards: give it the price you paid and the percent off, and it finds the original price.
How to use it
- Enter the priceThe original ticket price, before any reduction. Or switch to Original price mode and type the sale price you actually paid instead.
- Enter the discountThe percentage off. If there is a second discount on top (a member code, a sale-on-sale) add it in the third box.
- Read the savingWhat you save leads, with the final price and the true combined discount beside it. In reverse, the original price appears there instead.
The stacking illusion
The one genuinely counter-intuitive thing about discounts is how they combine. Two discounts multiply, because the second one acts on the smaller, already-reduced price. "Extra 10% off sale items" sounds like it adds ten points to the discount; it actually adds ten percent of whatever was left. On a 25% sale that is 7.5 points, not 10.
Retailers do not stack discounts by accident, the gap between the perceived and real reduction is the point. This calculator prints the combined percentage next to the price precisely so that gap is visible. Not because 32.5% off is a bad deal, but because deciding on the real number beats deciding on the implied one.
Deciding quickly at the shelf
In a shop, the useful skill is speed, not precision. Convert "percent off" to "percent paid" and multiply once: 30% off means times 0.7. Round the price first: 30% off 79.90 is roughly 0.7 × 80, call it 56. Being within a euro in three seconds beats being exact in thirty, and the till will be exact for you anyway.
Working backwards from the receipt
Sometimes the question runs the other way: you paid 34.99 in a 30% sale and want to know what the shop used to charge. Adding 30% back on gives 45.49, which is wrong, because the 30% was taken from the bigger original figure, not from what you paid. The Original price mode divides instead, 34.99 ÷ 0.7 = 49.99, and shows what the discount was worth in money.
When percent off is not the real question
A discount tells you the price fell; it cannot tell you the thing is worth buying. The honest comparisons are the final price against other sellers, and unit price against alternatives: 40% off a large pack can still cost more per unit than the plain small one. For those comparisons, the percentage calculator next door does of-what and difference-between in one place.
Questions people ask
How do I work out 20% off in my head?
Find 10% by moving the decimal point one place, then double it. 20% off 45 is: 10% is 4.50, doubled is 9, so you pay 36. The 10%-first trick handles most discounts: 5% is half of it, 15% is one-and-a-half, 25% is a quarter directly.
Why is 25% off plus 10% off not 35% off?
Because the second discount applies to the already-reduced price, not the original. 100 at 25% off is 75; another 10% takes off 7.50, not 10, landing at 67.50, which is 32.5% off. The gap grows with bigger numbers: 50% plus 50% is 75% off, not free.
Is a discount before or after tax?
Discounts normally apply to the pre-tax price, and tax is charged on the reduced amount, so in VAT countries, the sticker maths works out the same either way. If you need the tax split out, the VAT calculator one tool over does exactly that.
What is the difference between 25% off and paying 75%?
Nothing, they are the same statement, and flipping between them is often easier. 35% off means paying 65%, so multiply by 0.65 and you are done in one step.
How do shops make discounts look bigger?
Stacking is the main trick, since intuition adds the percentages while reality multiplies them. The other is anchoring against a rarely-charged 'original' price. The defence is the same for both: ignore the claimed percentage and look at the final price and the saving, the two figures this tool prints together.
How do I find the original price from the sale price?
Divide the sale price by one minus the discount, never add the percentage back on. Something bought for 34.99 at 30% off cost 34.99 ÷ 0.7 = 49.99 originally. The Original price mode does this division for you and shows the amount the discount was worth.
Which is better, three for two or 30% off?
Three for two is a 33.3% saving, but only if you wanted all three items. Buy two and you have paid full price. Flat percentages apply to whatever you put in the basket, so the comparison that settles it is the cost per unit at the quantity you actually need.