Percent Off Calculator

Take a percentage off a price and see both what you save and what you pay. Or work backwards from a sale price to the discount.

Take a percentage off

You save

$20.00

You pay this share

75%

You pay

$60.00

80 × 0.75

Discount calculator — find the discount from two prices

You can see both prices on the tag but not the percentage.

Work the discount out backwards

You save

$20.00

Discount

25%

(80 − 60) ÷ 80 × 100

The quick way to take a percentage off

Do not work out the discount and then subtract it. Multiply once by what is left:

Final price = Price × (1 − Discount ÷ 100)

For 25% off, you pay 75%, so multiply by 0.75. One step, no subtraction, far less room for a slip.

Worked example — 25% off $80

100 − 25 = 75, so you pay 75%

80 × 0.75 = 60

You pay $60 and save $20.

Working backwards from a sale price

Discount = (Original − Sale) ÷ Original × 100

From $80 down to $60: the gap is $20, and 20 ÷ 80 × 100 = 25% off.

Stacked discounts do not add up

This is the one that costs shoppers money. "20% off, then another 10% off at the till" is not 30% off.

  • After 20% off you pay 0.8 of the price.
  • Another 10% off that leaves 0.9 of the remainder.
  • 0.8 × 0.9 = 0.72, so you pay 72% — a 28% discount.

Stacked discounts multiply. The order does not matter, but the total is always less than the sum of the two.

Doing it in your head

  • 50% off is half. 25% off is half, then half again off the original.
  • 10% off is the decimal point moved one place left. 20% is that doubled, 5% is half of it, and 15% is 10% plus 5%.
  • 33% off is close enough to a third for a shelf-edge estimate.

Where sales tax fits

Tax is charged on what you actually pay, so the discount comes off first. A $80 item at 25% off with 8% sales tax costs 60 × 1.08 = $64.80.

Common questions

How do I take a percentage off a price?
Multiply the price by 1 minus the discount as a decimal. For 25% off $80: 80 × 0.75 = $60. You save $20.
How do I work out the discount from a sale price?
Subtract the sale price from the original, divide by the original, then multiply by 100. From $80 down to $60: 20 ÷ 80 × 100 = 25% off.
Do two discounts of 20% and 10% add up to 30% off?
No. Stacked discounts multiply rather than add. 20% then 10% off leaves 0.8 × 0.9 = 0.72 of the price, which is 28% off, not 30%.
Is sales tax added before or after the discount?
After. The discount comes off the ticket price first, and tax is charged on what you actually pay.
What does 'up to 70% off' really mean?
It means at least one item is 70% off. It says nothing about the rest. Work out the discount on the specific item you want.