Discount Calculator
Open toolCalculate the sale price after a discount, or the original price before one.
Two questions about sale prices: what will I pay after a percentage discount (and how much do I save), and what was the original price before a discount. Both sections are live and independent.
How it works
Price after discount: Sale price = Original price × (1 − Discount ÷ 100); the saving is Original − Sale price.
Original price before discount runs it backwards: Original price = Sale price ÷ (1 − Discount ÷ 100).
Results are rounded to two decimals, and trailing zeros are dropped, so 64.00 is shown as 64. Amounts in this tool always carry a dollar sign; it is only a label, so read it as whatever currency you are using. The site-wide currency setting does not change it.
How to use it
- To find a sale price, use the first section: enter the Original price and the Discount %.
- To find what something cost before it was reduced, use the second section: enter the Sale price and the Discount %.
- Read the result and click Copy to copy it.
Options & controls
Price after discount
- Original price
- The full price. Must be 0 or more. Default: 80.
- Discount %
- The percentage off, for example
20. Must be 0 or more. Default: 20. - Result
- “Sale price: $64 — you save $16”. A dash appears if either box is empty or invalid.
Original price before discount
- Sale price
- The price you are paying now. Must be 0 or more. Default: 64.
- Discount %
- The percentage that was taken off. Must be at least 0 and less than 100. Default: 20.
- Result
- “Original price: $80”. A dash appears if either box is empty or invalid, or the discount is 100% or more (the original cannot be worked out from a free item).
Buttons
- Copy
- Beside each result. Copies the result sentence.
- Reset
- In the title row. Restores the four sample values.
Tips & guidelines
- Successive discounts do not add up. 20% off followed by another 10% off is 28% in total, not 30%: apply each in turn (run the result through the calculator again).
- If tax is added at the till, it applies to the discounted price, so it is best worked out separately after this.
- To compare two offers, such as “30% off” and “buy one, get one half price”, calculate each as a final price rather than as a percentage.
- To check a claimed discount, enter the original and sale prices in the Percentage Calculator's “percentage change” section.
Limits
- One discount at a time. There is no combined-discount, coupon, or tax option.
- The dollar sign is fixed and cannot be changed; the numbers are not converted between currencies.
- A discount above 100% in the first section produces a negative price rather than an error.
Saved in your browser
Nothing. Values return to the sample numbers when you refresh.