Discount Calculator Formula
Understand the math behind the discount calculator. Each variable explained with a worked example.
Formulas Used
You Save
savings = original_price * discount_percent / 100Sale Price
final_price = original_price - savingsVariables
| Variable | Description | Default |
|---|---|---|
original_price | Original Price(USD) | 120 |
discount_percent | Discount(%) | 25 |
How It Works
How Discounts Are Calculated
Savings = Original Price × Discount% / 100
Sale Price = Original Price - Savings
Use this calculator anytime you see a percentage-off sale and want to know the exact dollar amount you will save and the final price you will pay at checkout. Keep in mind that discounts are applied before sales tax in most jurisdictions, so the tax is calculated on the reduced price, not the original.
Worked Example
A $120 item at 25% off.
- 01Savings = $120 × 25% = $30
- 02Sale price = $120 - $30 = $90
Frequently Asked Questions
How do stacked discounts work?
When two discounts are applied sequentially (e.g., 20% off then 10% off), they are not additive. Apply the first discount, then apply the second to the reduced price.
How do I calculate the discount if I only know the original and sale price?
Subtract the sale price from the original price to get the savings amount, then divide by the original price and multiply by 100. For example, if an item dropped from $80 to $60, the discount is ($80 - $60) / $80 x 100 = 25%.
What is the difference between a discount and a markup?
A discount reduces the selling price for the buyer, while a markup increases the cost price to set a selling price for the seller. They are calculated from different bases: discounts from the retail price, markups from the wholesale cost.
Learn More
Guide
How to Calculate Percentages
Learn how to calculate percentages step by step, including finding a percentage of a number, percentage increase or decrease, and converting between fractions and percentages. Master percentage calculations for everyday use in finance, school, and shopping.
Ready to run the numbers?
Open Discount Calculator