Discount calculator
Calculate a sale price, savings and the effective percentage of two successive discounts.
No thousands separators. Prices: 0–1e100. Discounts: 0–100%. Values are unitless; no tax or currency rounding.
Runs in your browser. Inputs are not uploaded or saved.
How to use
Choose a mode, enter values or load the example, then copy or download your result.
Rules and worked example
A 20% discount on 100 gives 80. An additional 10% discount applies to 80, producing 72: total savings are 28, or 28%. Successive discounts multiply the remaining fractions rather than adding the percentages.
Questions and answers
Does the calculator include tax or currency rounding?
No. Results are unitless and rounded to 12 significant digits for display. Apply your own currency precision and tax rules separately. A zero original price produces zero savings and an effective discount of zero by convention. Leave the second discount blank to calculate only the first.