Percentage Calculator

Calculate discounts, tips, VAT, percentage change, and percentage difference. Results update as you type.

Discount Calculator

Work out the sale price and the amount saved on any item. Set the row below to Decrease, type the original price, then the discount percentage. The discounted price appears as you type. Useful for shopping, retail markdowns, Black Friday deals, or any "X% off" offer.

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How a discount is calculated

A discount is just a percentage decrease applied to a starting price. The formula is sale price = original price × (1 − discount ÷ 100). The amount saved is the difference between the original and the sale price, or equivalently original × discount ÷ 100.

On this page the calculator is pre-scoped to a single row: the Increase / Decrease by mode. Pick Decrease for a discount (sale price), or Increase if you want to apply a markup instead. Both directions use the same formula with a flipped sign.

Worked example

An $80 jacket is on sale at 25% off. Set the toggle to Decrease, enter 80 as the base and 25 as the percentage. The result is 60, the sale price. The shopper saves $20.

Discount Calculator FAQ

What does "% off" actually mean?
"25% off" means the price is reduced by 25 percent of itself. A $40 item at 25% off becomes $40 − ($40 × 0.25) = $30. The number after "off" is always applied to the original (pre-discount) price, not the sale price.
How do I calculate a 20% discount?
Set the row to Decrease, enter the original price, and enter 20 for the percentage. The result is the price after the 20% discount. To see the savings, multiply the original price by 0.20, or simply subtract the result from the original.
How do I find the original price from a discounted price?
If you know the sale price and the discount percentage, the original price is sale price ÷ (1 − discount ÷ 100). For example, a $60 jacket sold at 25% off had an original price of 60 ÷ 0.75 = $80. You can compute this with the standard percentage calculator using the "X is Y% of what?" row, with X = sale price and Y = (100 − discount).
Can I stack two discounts?
Stacked discounts compound, they don't add. A 20% discount followed by another 10% off is not a 30% discount; it's 0.80 × 0.90 = 0.72, so 28% off the original. To compute it on this page, first decrease by 20%, copy the result back into the base field, then decrease by 10%.
Is this discount calculator free?
Yes. PercentCalc.app is free, runs entirely in your browser, has no signup, no ads, and works on any device.

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