One discount
Multiply the price by 1 minus the discount divided by 100. A 25% discount multiplies by 0.75.
The saving is the original price minus the price you pay.
Two discounts on top of each other
A second discount applies to the already reduced price, not the original. Multiplying the two multipliers gives the combined effect.
25% off then a further 10% off is 0.75 x 0.90 = 0.675, so the overall discount is 32.5%, not 35%.
Worked examples
A price of 120 with 25% off costs 120 x 0.75 = 90, a saving of 30.
With a further 10% off, the price becomes 90 x 0.90 = 81, a saving of 39 and an overall discount of 32.5%.
Adding 20% sales tax to the 90 gives 108, of which 18 is tax.
Inputs for the discount calculator
Price before discount
The full price on the label, before anything is taken off. It must be more than zero.
Discount
The percentage taken off the full price. Type 25 for 25% off.
Extra discount on top
A second reduction applied to the already discounted price. Leave it at 0 if there is only one discount.
Sales tax or VAT
Added to the discounted price. Leave it at 0 if the price already includes tax.
CALCULATOR QUESTIONS
Discount calculator questions
How do I work out a 25% discount?
Multiply the price by 0.75. A price of 120 becomes 90, a saving of 30.
Do two discounts add up?
No. The second applies to the reduced price. 25% then 10% is 32.5% overall, not 35%.
Should tax be added before or after the discount?
Discounts come off the price first and tax is charged on what you actually pay, which is the order this calculator uses.
How do I find the original price from a sale price?
Divide the sale price by the multiplier. A price of 90 after 25% off came from 90 / 0.75 = 120.