What Is a Discount Calculator?
A discount calculator finds the final price of an item after a percentage discount is applied, and optionally adds sales tax on top — helpful for shopping, sales planning, or comparing deals.
How to Use the Discount Calculator
- Enter the original price of the item.
- Enter the discount percentage.
- Optionally add a sales tax rate if tax applies after the discount.
- See exactly how much you save and the final price instantly.
Discount Formula
Worked Example
Original price: $80.00
Discount: 25%
Savings: $80 × 0.25 = $20.00
Final price: $80 − $20 = $60.00
Understanding Your Results
You Save shows the dollar amount taken off the original price. After Discount is the discounted price before any tax. If you add a sales tax rate, Final (with Tax) shows the true out-the-door price, since tax is normally calculated on the discounted price, not the original.
Stacking Multiple Discounts
Discounts don't simply add together — a 20% discount followed by another 10% discount is not a 30% total discount. Each discount applies to the already-reduced price, so the combined effect is smaller than adding the percentages directly (in this example, about 28% total).
Common Mistakes to Avoid
- Adding two discount percentages together instead of applying them sequentially.
- Calculating tax on the original price instead of the discounted price.
- Assuming a percentage-off discount is always the best deal — compare unit price or per-item cost when quantities differ.
Frequently Asked Questions
Multiply the original price by (1 − discount percentage as a decimal). For example, $80 with a 25% discount is $80 × 0.75 = $60.
In most places, sales tax is calculated on the discounted price, not the original price — this calculator applies tax after the discount by default.
They apply sequentially, not additively. A 20% discount followed by a 10% discount results in a combined discount of 28%, not 30%, since the second discount applies to an already-reduced price.
Multiply the original price by the discount percentage (as a decimal) to find the dollar amount saved.
Not necessarily — compare the actual final price per unit, especially when comparing different package sizes or original prices.