Discount Calculator — Free Online Tool

The Discount Calculator works out the final price after a percentage or fixed-amount reduction, showing what you pay and how much you save.

The case worth understanding is stacked discounts, because they do not add up the way the signage implies. An extra 20 percent off an item already reduced by 30 percent is not 50 percent off — the second discount applies to the already-reduced price, giving 0.7 multiplied by 0.8, which is 0.56, so 44 percent off rather than 50. This gap widens as the discounts get larger, and it is the arithmetic behind a great deal of retail signage.

Working backwards is the other common need: given a sale price and the original, what discount is that actually? Retailers frequently express the same reduction in whichever direction sounds larger, and converting between the two is the fastest way to compare offers described differently.

Worth a note of scepticism: in many markets the "original price" a discount is calculated from is a reference price the item was rarely sold at. A 60 percent reduction from an inflated anchor can be a worse deal than 20 percent off a realistic price, which is why comparing the final price against other sellers beats comparing discount percentages.

All calculation happens in your browser instantly, with no data sent anywhere.

Our Discount Calculator is completely free to use with no signup required. For this tool, processing runs in your browser — your files and data stay on your device and are not uploaded to our servers.

Whether you are a developer, designer, student, or business owner, this tool is designed to save you time and make your workflow more efficient. Bookmark this page to access it whenever you need it — it will always be free.