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Discount & Sale Price Calculator

What you actually pay after a discount — including the second discount that does not add the way the sign implies.

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Discount & Sale Price Calculator

$90.99
You save $39.00 (30%)

Applies the discounts in the order shown, then tax on the reduced price. Retailer terms differ — some exclude already-reduced items from a second discount, and some jurisdictions tax differently — so treat the total as an estimate until the till agrees.

Common discounts at a glance

Sale price by original price and discount percentage
Original10% off25% off30% off50% off70% off
$20$18.00$15.00$14.00$10.00$6.00
$50$45.00$37.50$35.00$25.00$15.00
$100$90.00$75.00$70.00$50.00$30.00
$250$225.00$187.50$175.00$125.00$75.00
$500$450.00$375.00$350.00$250.00$150.00

Stacked discounts: the arithmetic retailers rely on

“40% off, plus an extra 25% off at checkout” reads like 65% off. It is not. The second discount applies to the already-reduced price:

  • $200 at 40% off → $120
  • $120 at a further 25% off → $90
  • Total saved: $110, which is 55% off — not 65%.

The general rule: multiply what remains. 0.60 × 0.75 = 0.45, so you pay 45% and save 55%. Two discounts never add up to their sum, and the gap widens as the percentages grow.

Working backwards from a sale price

To find the original price from a discounted one, divide rather than multiply. An item marked $63 after 30% off was 63 ÷ 0.70 = $90. Adding 30% back to $63 gives $81.90, which is the same mistake as the increase-then-decrease trap on the percentage calculator page.

Is the bigger pack still cheaper on sale?

A discount changes the answer to a question a percentage cannot settle: which option is actually better value. A 30%-off 500 g jar and a full-price 1 kg jar need to be compared per gram, not per sticker. That is the unit price calculator — and in a shop, with two products in front of you, it is the clearest case for having two calculators on one screen.

Frequently Asked Questions

How do I calculate a discount?
Multiply the price by the discount percentage and divide by 100 to get the saving, then subtract it. Or go straight to the sale price: price × (1 − discount ÷ 100). $129.99 at 30% off is 129.99 × 0.70 = $90.99.
Is 30% off plus 20% off the same as 50% off?
No. The second discount comes off the already-reduced price: 0.70 × 0.80 = 0.56, so you pay 56% and save 44%.
How do I find the original price from a sale price?
Divide by the remaining fraction. An item costing $63 after 30% off was 63 ÷ 0.70 = $90. Adding the percentage back on gives the wrong answer.
Does this calculator handle sales tax?
Yes. Enter a tax percentage and it is applied to the discounted price, which is the normal order — tax is charged on what you actually pay, not the pre-discount price.

Compare two deals at once

Two independent calculator panels, free, so both prices stay on screen. No ads, ever.

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