Finance
Discount Calculator
Apply a percentage discount to a price or reverse-engineer the discount rate from the original and sale price. Free, instant, no signup.
Enter original price and discount % to see the final price.
All calculations happen in your browser. Nothing is stored.
✳ Free · No signup · Runs in your browser — we never store your numbers
Small business guide
What this tool helps you do
Use this discount calculator two ways: (1) apply a percentage discount to any price and see the final amount and savings, or (2) enter the original price and the final sale price you paid to discover the real discount percentage.
Discount math is simple but easy to get wrong when you need to compare offers, run promotions, or reverse-engineer competitor pricing. This tool gives you both directions instantly.
How to use this tool
- 1
Use 'Apply discount' to start from the regular price and a discount percentage.
- 2
Use 'Find the discount %' when you see a sale price and want to know what percentage off the original it actually is.
- 3
Results update instantly. All math happens in your browser.
Formula
Discount amount = original price × (discount % ÷ 100). Final price = original price − discount amount. Reverse: discount % = (original − final) ÷ original × 100.
- Always use the pre-discount price as the base when calculating the percentage off.
- A '50% off' sale on a price that was already marked up can still leave the seller with healthy margin.
- Stacking discounts (e.g. 20% off + extra 10%) is not the same as a flat 30% off — always calculate the compounded effect.
Examples
Retail promotion
A jacket normally sells for $120. The store is running 25% off.
Inputs
- Original: $120
- Discount: 25%
Result
You pay $90. You save $30.
25% off $120 is a $30 discount. The store still receives $90 before any other costs.
Reverse engineer a sale
A laptop is advertised at $850. You remember the regular price was $1,000.
Inputs
- Original: $1,000
- Final: $850
Result
This is a 15% discount ($150 off).
Always calculate the real percentage. 'Save $150' sounds different than '15% off' depending on the original price.
Key terms
Discount percentage
The percentage reduction from the original price. A 20% discount on $100 means you pay $80.
Final / sale price
The price the customer actually pays after the discount is applied.
How to interpret the result
Discounts reduce gross profit directly
A discount comes out of the gross profit you would have made. Before discounting heavily, check your margin (use the Profit Margin Calculator). A 20% discount on a 30% margin item cuts your gross profit by two-thirds.
Not all discounts are equal
A 30% discount on a slow-moving item can be smart. The same discount on your best-seller can destroy profitability. Use the calculator to model the real impact before you announce the promotion.
Common mistakes
- Calculating the discount from the final price instead of the original price.
- Forgetting that stacked discounts (20% + 10%) equal more than 30% off.
- Running deep discounts without checking whether the remaining margin still covers overhead and profit goals.
Frequently asked questions
How do I calculate percent off?+
Subtract the sale price from the original price, divide the difference by the original price, then multiply by 100. Or just use the reverse mode in this calculator.
Is a discount the same as markup in reverse?+
Not exactly. Discount is always taken from the selling price. Markup is added to cost. Use the Markup Calculator and Discount Calculator together when planning promotions.
Does this tool include tax?+
No. Calculate the discounted pre-tax price here, then use the Sales Tax Calculator to add tax on top.