Discount Percentage Calculator
Three modes to help with discounts: find the sale price after a discount, calculate what percentage discount you received, or work backwards to find the original price from a discounted price.
What is X% off Y?
Original price + discount % → sale price and saving
Enter the original price and the discount percentage.
Related: Discount Calculator · Percentage Increase
What discount % is this?
Original price + sale price → discount %
Enter the original price and the discounted sale price.
What was the original price?
Sale price + discount % → original price
Enter the sale price you paid and the discount percentage that was applied.
How the Discount Percentage Calculator works
This page provides three related discount calculations in one place. The first mode works out the sale price and saving when you know the original price and the discount percentage. The second mode does the reverse — given the original and sale prices, it tells you exactly what percentage was taken off. The third mode reconstructs the original price from a discounted price and a known discount percentage.
Understanding discount percentages is particularly useful during UK sale events such as Black Friday, the January sales, or seasonal clearances. Retailers are required by the Competition and Markets Authority to base percentage discount claims on genuine previous prices, but comparing the calculated discount yourself is a reliable way to verify whether a deal is as good as advertised.
The reverse calculation — finding the original price from a sale price and discount percentage — is also handy when you want to understand how much a VAT-inclusive item cost before a trade discount was applied, or when checking price history on shopping comparison sites.
Frequently asked questions
How do I find the percentage discount?
To find the percentage discount, subtract the sale price from the original price to get the saving, then divide that saving by the original price and multiply by 100. For example, if an item was £80 and is now £60, the saving is £20. £20 ÷ £80 × 100 = 25% discount.
How do I calculate the original price after a discount?
To reverse a percentage discount and find the original price, divide the sale price by (1 minus the discount expressed as a decimal). For example, if you paid £60 after a 25% discount: £60 ÷ (1 − 0.25) = £60 ÷ 0.75 = £80. This works because the sale price represents the remaining percentage of the original after the discount was applied.
What is a good discount percentage?
Whether a discount is 'good' depends on the product and the retailer's normal pricing. In UK retail, discounts of 10–20% are common in regular sales, while 30–50% is typical during major events such as Black Friday or end-of-season clearances. Anything above 50% is unusual and worth scrutinising — the original price may have been inflated to make the discount appear larger than it genuinely is.
How do retailers use discounts strategically?
Retailers use several pricing tactics around discounts. Anchoring involves displaying a high original price to make the discounted price seem more attractive. Time-limited offers create urgency. Multi-buy promotions (such as 3 for 2) encourage higher spending. In the UK, the Competition and Markets Authority requires that advertised sale prices reflect genuine previous pricing, though enforcement can be inconsistent. Comparing unit prices and using price-tracking tools can help identify genuinely good deals.