Discount Calculator

Enter Calculation

Calculate: List Price Discount % Sale Price

List Price ($)

Discount (%)

Sale Price ($)

Enter any two of the three values; the field selected in "Calculate:" is the one we compute. Discount is a percent (e.g. 40 = 40%).

Formula

Show calculation steps (2)

1. Discount Percent

   

   Percentage off given the list price and sale price.

2. List Price

   

   Original price recovered from the discount and sale price.

Results

List Price

$83.33

original price before discount

List Price	$83.33
Discount	40.00%
Sale Price	$50.00
Amount Saved	$33.33

What this calculator does

This discount calculator solves the three-way relationship between a product's list price (the original price), the discount percent (how much is taken off), and the sale price (what you actually pay). Enter any two of these values, choose which one to calculate, and the tool returns the missing value along with the amount saved in dollars. The math is currency-agnostic, so the dollar sign is purely cosmetic — it works for any single currency.

How to use it

Pick the quantity you want to find in the "Calculate:" dropdown (List Price, Discount %, or Sale Price). Fill in the other two fields and submit. The discount is entered as a percent number, so type 40 for 40% (not 0.40). All results are shown to two decimal places.

The formula explained

The core identity is $$\text{Sale Price} = \text{List Price} \times \left(1 - \frac{\text{Discount}}{100}\right)$$ Dividing the discount by 100 converts the percent into a fraction. Rearranging this single equation gives every mode:

• Solve for sale: \(S = L \times \left(1 - \frac{D}{100}\right)\)
• Solve for discount: \(D = \frac{L - S}{L} \times 100\)
• Solve for list price: \(L = \frac{S}{1 - \frac{D}{100}}\)

The amount saved is always \(L - S\). Two domain guards apply: the discount mode needs a non-zero list price (otherwise the percentage is undefined), and the list-price mode breaks at a 100% discount (dividing by zero), since a 100% discount makes the sale price zero for any list price.

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The sale price is the list price minus the discount amount.

Worked example

You paid $50 for an item marked 40% off and want the original price. Convert the discount: \(40/100 = 0.40\). Then $$\text{List Price} = \frac{50}{1 - 0.40} = \frac{50}{0.60} = 83.33$$ The amount saved is \(83.33 - 50.00 = 33.33\).

A worked example: the original price is reduced to the discounted sale price.

FAQ

Do I enter the discount as 40 or 0.40? Enter it as a whole percent: 40 means 40%.

Can the discount be more than 100%? Mathematically yes, but it is not economically meaningful — it would imply a negative sale price, so treat values above 100% as invalid.

Does the currency matter? No. The calculation only uses ratios and differences, so it works identically for any currency.