Discount calculator
Work out the dollar saving and sale price from a percentage off.
What the result means
A discount is a percentage of the original price, subtracted from that original. 15% off $240 is $36, leaving $204 — not 15% of some other figure.
How it is calculated
Sale = original × (1 − %/100). Saving = original − sale
- Original: The ticketed price before the markdown.
The percentage always uses the original as the base. Two successive 10% discounts are not 20% off.
Assumptions
- Estimates only — not tax, legal, credit or financial advice. Check the official source or your contract before relying on a figure.
- A single percentage off one price, not stacked coupons.
Worked example
15% off $240
A jacket on sale.
- Saving
- $240 × 15% = $36
- Sale price
- $204
That is the decrease mode of a percentage, specialised for a price ticket.
GST sits on the price you actually pay
If a ticketed price already includes GST, the discounted price usually still includes GST. Use the GST calculator if you need the tax component of the sale price.
Two successive discounts multiply. 10% off then another 10% off is 19% off the original, not 20%. Reversing a markup is a different operation again: a 25% markup reversed is a divide by 1.25, not a 25% sticker, which is why a “25% off” sale on a 25% markup sells below cost.
Questions
How do I stack two discounts?
Apply the first sale price as the new original. 10% then 10% is 19% off, not 20%.
Is 50% off the same as reversing a 50% markup?
No. A $100 cost marked up 50% is $150. Half of $150 is $75, which is below cost. To reverse a 50% markup, divide by 1.5.
Read the background
These guides explain the rules behind this calculation in full, without any inputs to fill in.
- How GST works in AustraliaAdding GST is ten per cent; removing it is one eleventh. Why the two are different, plus GST-free items, invoices and rounding.7 min read
- Markup versus margin, and why they are never the same numberA 25% markup is a 20% margin. How Australian small businesses mix the two up, and how GST sitting on top changes the cash in the till.8 min read
Related calculators
- GSTAdd 10% GST, remove GST from an inclusive price, or see the GST component using the Australian 1/11 rule.
- PercentageFind a percentage of a number, reverse a percentage, or calculate percentage increase, decrease and difference.
- Margin & markupSee why a 25% markup is a 20% margin, and price from either figure.
Sources
business.gov.au
Finance and accounting for business
Last reviewed 2026-08-19
Everyday · Last reviewed 19 August 2026
Estimates only. Not tax, legal or financial advice. Check official sources before relying on a figure.
Spotted a mistake? Contact us.
Printed from OzCalc (ozcalc.com). Last reviewed 19 August 2026. Estimates only — not tax, legal or financial advice.