data tool
Discount calculator
A discount takes its percentage off the original price; a second discount comes off the already reduced price, so 20% off and then 10% off is 28% off, not 30%. Type a price and one or two discounts to get the sale price, the saving, the true percentage off and a price list for a sale sign.
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- Runs on your device, nothing is uploaded
- Free, no sign in
- No watermark, no file limit
How it works
- 1
Enter the original price
Use the price before the sale, in dollars or any currency.
- 2
Add the discount
Type the percentage off. Add a further discount if the offer stacks, such as an extra 10% off sale items.
- 3
Add tax if needed
If the price excludes tax, enter the rate and the tool adds it after the discounts.
- 4
Copy the was and now line
Copy the result as a short was and now line, or read the price list for a sign.
The discount formula
The sale price is the original price times one minus the discount. Twenty five percent off $80 is 80 times 0.75, or $60, and the saving is $20. To find the percentage off from two prices, divide the saving by the original price: $20 off $80 is 25%. People often reach for the wrong base, dividing the saving by the sale price instead, which turns the same $20 into 33%. The calculator always measures from the original price, which is the figure a was and now sign compares against.
Stacked discounts multiply, they never add
When a second discount applies to an already reduced price, the two multiply. Twenty percent off and then a further 10% off leaves 0.8 times 0.9, or 72%, of the original, which is 28% off in total, not 30%. Fifty percent off and then another 50% off is 75% off, not free. Retailers word these offers as an extra 10% off sale prices for exactly this reason, and a customer who expects the sum will be surprised at the register. The note under the result shows both figures whenever a second discount is set.
Tax goes on after the discount
Sales tax, GST and VAT are charged on the price actually paid, so they come after every discount. If a $100 item before tax is 20% off and GST is 10%, the customer pays $80 plus $8 GST, $88. Taking the discount off a tax inclusive price gives the same answer, because the percentages multiply in either order. Where it matters is in signs and quotes: say whether a sale price includes tax, and in Australia consumer prices generally should.
Showing a was and now price fairly
Consumer law in Australia and the UK treats misleading price claims seriously. A was price should be a genuine price the item actually sold at for a reasonable period before the sale, and the saving should be what customers really save. Inventing a higher was price to make a discount look bigger can breach the Australian Consumer Law and, in the UK, the unfair commercial practices rules in the Digital Markets, Competition and Consumers Act 2024. Keep a record of the original price and how long it applied.
A price list for a sale sign
The table under the result lists the sale price and saving at 10%, 15%, 20%, 25%, 30%, 40%, 50%, 60% and 70% off your original price. It is the quick way to compare offers before choosing one, and the figures for a shelf talker or a sale flyer. A flyer made in the flyer builder can carry the offer, the dates and the price in large type; the sizes include A4 for a window and square and story sizes for social posts.
Discounts and your margin
A discount comes straight out of profit. On an item with a 40% margin, a 20% discount halves the profit per sale, so sales need to roughly double just to earn the same. Run the sale price through the profit margin calculator before committing to an offer, and decide on the minimum margin you are willing to sell at.
Limits
- Percentage discounts only. Buy one get one free and fixed dollar offers need working out by hand.
- Tax is applied after every discount, which is how a discounted sale is taxed.
- Prices are rounded to the cent for display only; the arithmetic keeps full precision.
- Whether a was price is fair to advertise is a legal question this tool cannot answer.
What it does not do
- It does not check your advertising against consumer law.
- It does not apply discounts to a whole price list file.
- It does not store your figures.
Questions people ask
How do I calculate a percentage off?
Multiply the original price by the percentage as a decimal to get the saving, then subtract it. Thirty percent off $45 is a $13.50 saving and a $31.50 price. Or multiply by one minus the discount directly: 45 times 0.7 is $31.50.
Is 20% off then 10% off the same as 30% off?
No, it is 28% off. The second discount applies to the reduced price, so you pay 80% of the price, then 90% of that, which is 72% of the original. On a $200 jacket that is $144, not $140. Stacked discounts always total a little less than their sum.
How do I work out the original price from a sale price?
Divide the sale price by one minus the discount. If an item is $60 after 25% off, the original price was 60 divided by 0.75, which is $80. Subtracting 25% of $60 from $60 gives the wrong answer, because the discount was taken from the larger original price.
Should the discount come before or after tax?
For the customer the answer is the same either way, because percentages multiply in any order: 20% off a tax inclusive price matches 20% off the pre tax price plus tax. On invoices, show the discount on the pre tax amount and calculate the tax on the discounted figure, which is how the tax is actually owed.
What discount do I need to give 25% off in total with two offers?
If the first offer is 10% off, the second needs to be about 16.7%, because 0.9 times 0.833 is 0.75. In general, divide the total you want to keep by what the first discount leaves: 0.75 divided by 0.9. The calculator lets you try values until the total shows 25%.
Make the sale flyer
Take what you made here into flyers.
Create a flyer with OneCraftMore tools like this
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Background reading: the question page on this.
Written and checked by the OneCraft team. Last checked .