Discount Calculator
Financial Calculators
Find sale price, savings, effective discount, and tax. Calculate percent or fixed discounts, stack a second deal, or work backward from sale price.
Calculation mode
Stack another discount
Enter prices and a discount to calculate the sale price.
How to use this tool
- Choose calculation mode. Choose "Original & Discount" to calculate a sale price, "Original & Final Price" to find the discount, or "Sale & Discount %" to recover the original price.
- Enter the original price. Type the full price before any discount.
- Enter the discount or sale price. Choose percentage off or fixed amount off for a single discount. You can add one more percentage or fixed discount; the second is calculated from the price after the first. In the other modes, enter the final price or the sale price and discount percentage.
- Optionally add sales tax. Enter a tax rate to see the final price after tax is applied to the discounted amount.
How to use the discount calculator
Choose a mode based on the prices you know. Original & Discount calculates a sale price from a percentage or fixed amount; Original & Final Price finds the discount from two prices; Sale & Discount % estimates the original price from what you paid and the advertised percentage. Results update as you edit the fields.
Percentage discounts use sale price = original × (1 − discount ÷ 100). For example, 25% off $80 is $80 × 0.75 = $60, a $20 saving. For a fixed coupon, subtract
the coupon value directly: $80 − $12.50 = $67.50. The effective percentage is the dollar
savings divided by the original price, multiplied by 100.
Stacking discounts means applying the next deal to the reduced price. If a $100 item is 20% off, it costs $80; an additional 10% takes off $8, leaving $72. The total savings are $28, or 28% of the original price—not 30%. A second fixed coupon is likewise subtracted from the post-discount price. The optional tax rate is applied after all discounts.
Finding a discount or original price
When you know both prices, use discount% = (original − final) ÷ original × 100.
An $80 item marked down to $60 is $20 cheaper, so $20 ÷ $80 × 100 = 25% off. To work in the
other direction, divide the sale price by the remaining fraction: original = sale price ÷ (1 − discount ÷ 100). Paying $80 after 20% off implies an original price of $100. A 100% discount cannot be
reversed because a zero sale price does not reveal the original amount.
Adding sales tax to a discounted price
The calculator applies tax to the fully discounted amount and reports both the estimated tax and total. For example, 30% off $100 leaves $70. With an 8.875% rate, estimated tax is $6.21 and the total is $76.21. Actual taxable amounts depend on local rules, item type, and coupon treatment, so use the checkout receipt for the final amount.
Common discount quick-reference
| Original price | 10% off | 20% off | 25% off | 30% off | 50% off |
|---|---|---|---|---|---|
| $10 | $9.00 | $8.00 | $7.50 | $7.00 | $5.00 |
| $25 | $22.50 | $20.00 | $18.75 | $17.50 | $12.50 |
| $50 | $45.00 | $40.00 | $37.50 | $35.00 | $25.00 |
| $100 | $90.00 | $80.00 | $75.00 | $70.00 | $50.00 |
| $200 | $180.00 | $160.00 | $150.00 | $140.00 | $100.00 |
| $500 | $450.00 | $400.00 | $375.00 | $350.00 | $250.00 |
Frequently asked questions
How do I calculate a discount percentage?
Divide the savings by the original price, then multiply by 100. Formula: discount% = (original − final) ÷ original × 100. For example, if an item costs $80 but was originally $100, the discount is (100 − 80) ÷ 100 × 100 = 20%.
What is 30% off $100?
$100 × (1 − 0.30) = $70. You save $30. You can verify: $30 ÷ $100 × 100 = 30% savings.
How do I calculate a fixed amount discount?
Choose Fixed amount off and subtract the coupon amount from the original price. For example, $100 − $12.50 = $87.50. The calculator also reports the equivalent percentage saved.
Why do two discounts add up to less than their percentages?
A second discount applies to the already reduced price. For example, 20% off $100 leaves $80; another 10% off takes away $8, so the final price is $72 and the effective discount is 28%, not 30%.
How do I calculate the final price including tax after a discount?
First apply the discount, then apply tax to the discounted price. For example, 20% off $50 = $40. With 8% tax: $40 × 1.08 = $43.20. This calculator does both steps automatically when you enter a tax rate.
Can I work backwards from the sale price to find the discount percentage?
Yes - switch to "Original & Final Price" mode, enter the original price and the sale price, and the discount percentage is calculated automatically.
How do I find the original price from a sale price and discount?
Choose Sale & Discount %, then divide the sale price by 1 minus the discount rate. If you paid $80 after 20% off, $80 ÷ 0.80 = $100. A 100% discount cannot be reversed because it could leave any original price at $0.