Discount Calculator
Calculate sale discount savings, final item prices, and extra percentage discounts.
Discount Result
Stacking, percentages, and what the sign means
A single discount is straightforward: 25% off $80 is $20 off, leaving $60. The arithmetic gets slippery when discounts stack, because successive percentages apply to a shrinking base. "30% off, then an extra 20%" is not 50% off — it is 0.7 × 0.8 = 0.56, so 44% off. The larger discount applied first gives the same final answer, though many people expect otherwise.
Percentage off and percentage of are the other common confusion. 40% off leaves you paying 60% of the price; going the other way, a price cut from $100 to $60 is a 40% discount, but restoring $60 to $100 requires a 67% increase. Percentage changes are not symmetric, which is why a 50% loss needs a 100% gain to recover.
Where tax applies, order matters to the final total: discounts are normally applied before sales tax, so the tax is charged on the reduced amount. And a discount only saves money against something you were going to buy anyway — "save $40" on an unneeded $60 item is a $60 expense, not a saving. The useful comparison is always against the alternative of not buying.
Frequently asked questions
How to calculate discount price?
Discounted Price = Original Price - (Original Price × Discount Percentage / 100).
How do I calculate a discount?
Multiply the original price by the discount percentage to get the saving, then subtract. A 30% discount on $80 saves $24, giving $56. Equivalently, multiply by (1 - discount), so $80 x 0.70 = $56 in a single step.
How do stacked discounts work?
They multiply rather than add. 20% off then a further 10% off is 0.8 x 0.9 = 0.72, a 28% total discount, not 30%. Order does not matter for percentage discounts, though it does when a fixed-amount coupon is combined with a percentage one - applying the percentage first usually gives the better outcome for the shopper.
How do I work out the original price from a sale price?
Divide by (1 - discount). An item at $56 after 30% off was $56 / 0.7 = $80. This is the check worth doing when a retailer advertises a large discount from a reference price that may never have been charged.