Updated on 29 September 2026 by the Proposal Expert editorial team
The saving and the sale price, or back to the price before the discount
To calculate a discount, multiply the price by the percentage and divide by 100, then subtract that amount from the price to get the sale price. This discount calculator, also known as a percent off or sale price calculator, does it for you in dollars or pounds. Enter the price and the percent off to see the saving and the price after the discount. If you only know the sale price, switch modes and it works back to the original price. Below you will find how to show a discount in a quote, whether it comes off before or after tax, and the US and UK rules on "was" prices.
Discount = price × percent ÷ 100. Sale price = price × (1 − percent ÷ 100). Original price = sale price ÷ (1 − percent ÷ 100).
At 15% off, the customer pays 85% of the price, so you multiply the price by 0.85. The discount is the difference between the old and the new price. To work backwards, divide the sale price by the same factor of 0.85. Adding 15% to the sale price gives too low a figure, because the discount was taken from the higher original price.
A design studio quotes a client $1,500 for a brand identity package and offers 15% off because the client books a second project at the same time. Multiply $1,500 by 0.15 to get the discount and subtract it from the list price. The table shows the discount and the price after the discount. That discounted figure is the net total on the quote, before any tax is added.
| Price before discount | $1,500.00 |
|---|---|
| Discount 15% | $225.00 |
| Price after discount | $1,275.00 |
If you only know the sale price and the percentage, divide the sale price by 1 minus the percentage divided by 100. At 15% off you divide by 0.85. An item that costs $68 after 15% off was $80 before, because $68 ÷ 0.85 = $80. The classic mistake is to add 15% back on. That gives $68 × 1.15 = $78.20, which is $1.80 short, because the discount was worked out on $80 and not on $68. When you know both prices, you can work out the percent off:
Two discounts in a row do not simply add up. The second discount applies to the price that is left after the first one. If a £100 item gets 20% off and then another 10% off, it costs £80 and then £72. The total discount is 28%, not 30%. To do it in one step, multiply the factors: 0.80 × 0.90 = 0.72. The order makes no difference. If a quote combines a volume discount with an extra project discount, show the combined amount on the discount line, so your client does not have to do the maths.
A discount is clearest when your client sees the list price, the discount and the net total separately. That shows what the work normally costs and what they save. Check your margin before you agree to a discount, because the whole discount comes off your profit. At a 30% margin, 15% off costs you half of your profit. In the UK, HMRC's VAT guide lists the rate of any cash discount offered among the details a VAT invoice must show, so it helps to use the same layout in the quote. Lay out the price table like this:
Under UK VAT and under New York sales tax, a discount given at the time of sale comes off first, and the tax is worked out on what is left. For a percentage discount the order makes no difference to the result. 15% off the price including 20% VAT gives the same total as 15% off the net price with VAT added afterwards. A fixed amount is different. On a £1,000 net price, £100 off the net amount gives £900 plus £180 VAT, which is £1,080. £100 off the £1,200 gross price gives £1,100, which is £20 more. So always say whether a fixed discount is before or after tax. Early payment discounts follow their own rules:
In the US, the FTC Guides Against Deceptive Pricing (16 CFR Part 233) describe when a price comparison is honest. A former price is a legitimate basis for a comparison if it is the actual, bona fide price at which the article was offered to the public on a regular basis for a reasonably substantial period of time. If a price is inflated only so that it can be cut again, the bargain is false. The guides cover these comparisons:
In the UK, the unfair commercial practices provisions of the Digital Markets, Competition and Consumers Act 2024 have applied to commercial practices since 6 April 2025. Under section 226, a practice is a misleading action if it gives false or misleading information, or if its overall presentation is likely to deceive the average consumer, even when the information is true. The CMA's guidance on these provisions (CMA207) names the price, the way it is calculated and the existence of a specific price advantage among the information that can mislead. The CMA's examples of misleading price reduction claims, which that guidance points to, include:
The final step is to put this price into a quote. Enter the list price, then the discount line with the percentage and the amount, then the net total, the tax and the total to pay. Check that the net total matches the price after discount from the calculator. Proposal Expert's price table calculates VAT and totals, including VAT per line. The free plan gives you 3 quotes and 3 digital signatures a month.
The discount is $10, because $50 × 20 ÷ 100 = $10, so you pay $40. The quick way is one step: $50 × 0.80 = $40.
Subtract the new price from the old price, divide the difference by the old price and multiply by 100. A price that drops from $60 to $45 is $15 ÷ $60 × 100 = 25% off.
Divide the sale price by 1 minus the discount percentage divided by 100. If you paid £90 after 10% off, the original price was £90 ÷ 0.90 = £100. Adding 10% to £90 gives £99, which is wrong.
No. After the first discount you pay 90%, and the second discount applies to that lower amount. Together you pay 0.90 × 0.90 = 81% of the price, so the total discount is 19%.
The UK provisions deal with unfair business-to-consumer practices, as the CMA's guidance explains, and the FTC guides are written about bargain advertising to the public. A discount you agree privately in a quote for a business client is a different situation. Keep the list price honest anyway, because your client will compare the quote with the invoice.