Money

Discount Calculator

Last updated: June 19, 2026

Blake Boege
Written by Blake Boege · Founder, Calculator Answers

A discount calculator is a practical consumer finance tool designed to compute the reduced price of an item during a sale or promotional event. It applies a percentage or fixed-amount discount to the original retail price, determining both the final sale price and the total monetary savings. Many versions also allow users to input a local sales tax rate to calculate the exact out-of-pocket cost at checkout. Shoppers and retailers use this calculator to quickly assess promotional deals, compare clearance options, and manage retail budgets.

Enter the original price and a discount percent. We compute the savings, the sale price, and an optional final total with sales tax — handy for shopping, deal evaluation, and budgeting.

Quick Answer

Calculate your savings and the final price after discounts. Enter the original price, the discount percentage, and any sales tax.

$

e.g. 120.00

%

Common breakpoints: 10%, 20%, 25%, 30%, 50%, 70%. · e.g. 25

%

Combined state + local rate. Leave at 0% to skip.

Sale price

After 25% off

$90.00

You save $30.00

Original price$120.00
Savings (25%)$30.00
Sale price$90.00
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Examples

$120 at 25% off

= $90 (saved $30)

$59.99 at 40% off + 8.25% tax

= $38.95 (saved $24.00)

$1,499 at 15% off

= $1,274.15 (saved $224.85)

How it works

We multiply the original price by the discount as a decimal to find your savings, subtract that from the original to get the sale price, and optionally add tax on the sale price.

Savings · price × (discount ÷ 100)

Sale price · price − savings

Final total · sale price × (1 + tax ÷ 100)

How to calculate a discount

Calculating a discount is a simple two-step process: find the discount savings amount, and subtract that amount from the original retail price to find the sale price.

  1. Convert the percentage to a decimal: Divide the discount percentage by 100 (e.g., 20% becomes 0.20).
  2. Calculate the savings: Multiply the original price by the decimal discount: Savings = Price × Decimal Discount.
  3. Subtract savings to find the sale price: Subtract the savings amount from the original price: Sale Price = Price − Savings.

Worked example: 30% off $150 with 8% sales tax

Let's say you are buying an item originally priced at $150 that is marked 30% off, and your local sales tax rate is 8%.

Step 1: Calculate the savings

Convert 30% to a decimal (0.30). Multiply by original price:
Savings = $150 × 0.30 = $45.00.

Step 2: Calculate the sale price

Subtract the savings from the original price:
Sale Price = $150 − $45 = $105.00.

Step 3: Calculate the sales tax

Convert 8% tax to a decimal (0.08). Multiply by the sale price (in most U.S. states, sales tax applies to the discounted price, not the original retail price):
Sales Tax = $105 × 0.08 = $8.40.

Step 4: Calculate the final total

Add the sales tax to the sale price:
Final Total = $105 + $8.40 = $113.40.

Sequential discounts (stacked coupons)

Stores sometimes offer stacked discounts (for example, "take an extra 20% off already-marked down 30% clearance items").

Important: You cannot add the percentages together (30% + 20% = 50%). They must be calculated sequentially:

  • First, apply the first discount (30% off $100 leaves $70).
  • Then, apply the second discount to the new, lower price (20% off $70 saves $14, leaving $56).
  • Your total final discount is 44% (saved $44), not 50%.

Common mistakes when calculating discounts

  • Adding stacked percentages: Confusing a sequential discount with a simple sum (e.g., thinking 20% off plus 10% off equals 30% off, when it actually equals 28% off).
  • Calculating tax on the original price: In most places, sales tax is assessed on the final transactional value (the sale price), not the original manufacturer retail price. Calculating tax on the original price makes you pay too much.
  • Confusing discount rate with paid rate: A 30% discount means you pay 70% of the price. If you want to compute the sale price in one step, multiply directly by the "paid rate" (Price × 0.70).

Related retail and shopping calculators

Plan your purchases and budget using these other useful financial tools:

Frequently asked questions

Multiply the original price by the discount percent expressed as a decimal. A 25% discount on $80 is 80 × 0.25 = $20 in savings, leaving $60 as the sale price.

In most U.S. jurisdictions, sales tax is applied after the discount, on the actual sale price paid. This calculator follows that order: sale price first, then tax on the discounted amount.

Subtract the sale price from the original price to find the savings. Divide the savings by the original price, and multiply by 100 to get the percentage: ($80 − $60) ÷ $80 × 100 = 25%.

Yes, but they must be applied sequentially, not added together. A 20% off followed by an extra 10% off is calculated as 100% × 0.80 × 0.90 = 72% of the original price (meaning a 28% total discount), not 30%.

A 20% discount on $100 means you save $20 ($100 × 0.20 = $20) and pay a sale price of $80 ($100 − $20 = $80).

First apply the first discount to the original price to get a temporary sale price. Then apply the second discount to that new temporary price. Do not add the percentages together (e.g., a 20% off and 10% off is a 28% total discount, not 30%).

Divide the sale price by (1 − discount rate as a decimal). If a shirt costs $60 after a 25% discount, the original price is $60 ÷ (1 − 0.25) = $60 ÷ 0.75 = $80.

To find the pre-tax price from a tax-inclusive total, divide the total by (1 + tax rate as a decimal). For example, if a total is $108 with an 8% tax rate, the pre-tax price is $108 ÷ 1.08 = $100.