Calculator guide
Find the dollar savings and sale price before sales tax from an original price and discount percentage.
Formula or method
Savings = original price × discount rate; sale price = original price × (1 − discount rate).
How to use this calculator
- Enter the original price before tax.
- Enter the advertised discount percentage.
- Review the savings and discounted price; add tax separately if needed.
Worked example
A 20% discount on $100 saves $20, leaving a pre-tax sale price of $80.
Understanding the result
The percentage is applied once to the original price. A store's coupon rules, exclusions, or stacking limits can change the checkout result.
Limitations and assumptions
- Does not add sales tax, shipping, fees, or conditional promotions.
- A discount above 100% would produce an invalid negative sale price and is not a meaningful retail scenario.
Frequently asked questions
Is 20% off the same as 20 percentage points?
No. A discount is a relative reduction from the original price.
How do I find the original price from a sale price?
For a single discount, divide the sale price by 1 minus the discount rate.
Can I apply two discounts?
Sequential discounts multiply: 20% then 10% leaves 72% of the original price, not 70%.
Sources
Educational information only; verify important decisions with a qualified professional.