Profit and pricing
Discount calculator
Work out the sale price and what you save from any two of original price, percent off and sale price. Below it: stacked discounts, and what a discount does to your margin and the extra sales it needs.
Any two values
Sale price and the amount saved from any two of original price, percent off and sale price.
Stacked discounts
A second calculator for one discount on top of another.
Margin impact
What a discount does to your margin and how many more units it needs.
Short answer
A discount calculator works out the sale price and the amount you save from an original price and a percent off. Multiply the price by the discount as a decimal to get the saving, then subtract it: 20% off 80 is 80 × 0.2 = 16 saved, a sale price of 64. Convertica's free calculator also finds the percent off and the original price.
- Sale price = original price × (1 - discount). Amount saved = original price × discount.
- Percent off = (original price - sale price) / original price × 100.
- To find the original price, divide the sale price by (1 - discount). Adding the percent back onto the sale price gives too low a number.
- Stacked discounts multiply rather than add: 20% off and then 10% off is 28% off, not 30%.
- For a seller, a discount comes straight out of profit per unit, so it can take far more extra sales than its size suggests to keep the same gross profit.
Discount calculator
Fill in any two fields and leave the third empty. Free, no sign-up, any currency. The result updates as you type, and nothing you type leaves your browser.
Sale price
64.00
Amount saved: 80 × 20% = 16.
Sale price: 80 - 16 = 64.
In one step: 80 × (1 - 20%) = 64.
Formula
amount saved = original price * discount
sale price = original price * (1 - discount)
percent off = (original price - sale price) / original price * 100
original price = sale price / (1 - discount)Stacked discount calculator
One discount on top of another, such as a sale price plus a coupon. Add a price to see each step.
Combined discount
28.00%
Price kept: (1 - 20%) × (1 - 10%) = 72.00% of the original.
Combined discount: 100% - 72.00% = 28.00%, not 30.00%: each discount comes off the price the one before left.
On 100: 100 - 20% = 80, then 80 - 10% = 72. You save 28.
Formula
combined discount = 1 - (1 - first) * (1 - second) * (1 - third)How do you calculate a discount?
To calculate a discount, multiply the original price by the percent off written as a decimal: that is the amount you save. Subtract it from the original price to get the sale price. 20% off 80 is 80 × 0.2 = 16 saved, so the sale price is 80 - 16 = 64.
amount saved = original price * discount
sale price = original price * (1 - discount)
percent off = (original price - sale price) / original price * 100
original price = sale price / (1 - discount)In these formulas the discount is a decimal, so 20% is 0.2. The shortcut in the second line saves a step: you pay 1 minus the discount, so 20% off means paying 80% of the price.
How to use the discount calculator
- Enter any two of the three values. Original price and percent off give the sale price. Original and sale price give the percent off. Sale price and percent off give the original price.
- Leave the third field empty. The calculator fills in the answer and shows each step so you can check it.
- For more than one discount, use the stacked calculator. Enter each percent in the order it is applied, with the price if you want the steps.
- If you are the seller, check your margin. The seller's discount calculator shows what the discount does to profit per unit and to the sales you need.
Discount calculator examples, worked step by step
The examples below show each kind of discount sum the calculator does, with the arithmetic written out. The prices are made up to show the method; they are not typical prices or typical discounts for anything.
Sale price from the original price and percent off
- Original price: 80. Percent off: 20%.
- Amount saved = 80 × 0.2 = 16.
- Sale price = 80 - 16 = 64.
How to calculate the discount percentage from two prices
To find the percent off, subtract the sale price from the original price, divide by the original price and multiply by 100. A price cut from 80 to 60 saves 20, and 20 / 80 × 100 = 25% off. Divide by the original price, never by the sale price.
How to find the original price from the sale price
To find the original price, divide the sale price by 1 minus the discount. A sale price of 60 after 25% off was 60 / 0.75 = 80. Adding 25% back onto 60 gives 75, which is too low, because the discount was a share of the larger original price.
| Discount | Sum | Amount saved | Sale price |
|---|---|---|---|
| 20% off 50 | 50 × 0.80 | 10.00 | 40.00 |
| 30% off 80 | 80 × 0.70 | 24.00 | 56.00 |
| 25% off 60 | 60 × 0.75 | 15.00 | 45.00 |
| 15% off 200 | 200 × 0.85 | 30.00 | 170.00 |
| 40% off 120 | 120 × 0.60 | 48.00 | 72.00 |
| 10% off 35 | 35 × 0.90 | 3.50 | 31.50 |
How do stacked discounts work?
Stacked discounts are applied one after another, each to the price the previous one left, so they multiply instead of adding. 20% off and then 10% off leaves 0.8 × 0.9 = 72% of the price, a combined discount of 28%, not 30%. The order makes no difference to the result.
- Start with the original price: 100.
- Take the first discount: 100 - 20% = 80.
- Take the second discount off that: 80 - 10% = 72.
- The combined discount is 100 - 72 = 28% of the original price.
A checkout can also combine discounts differently, for example by adding two coupons before applying them, or by taking a fixed amount off first. When the result matters, check how your store or the store you buy from applies them.
How to calculate a discount in Excel or Google Sheets
To calculate a discount in Excel or Google Sheets, put the original price in one cell and the discount in another, then multiply the price by 1 minus the discount. With the price in A2 and the discount in B2, the sale price is =A2*(1-B2). Format B2 as a percentage, so 20% reads as 0.2.
| To get | Formula | Result |
|---|---|---|
| Sale price | =A2*(1-B2) | 64 |
| Amount saved | =A2*B2 | 16 |
| Percent off from two prices | =(A2-C2)/A2 | 20% |
| Original price from sale price | =C2/(1-B2) | 80 |
How does a discount affect your profit margin?
A discount comes straight out of the seller's profit, because the cost of the product does not fall with the price. So the margin drops by more than the discount, and it takes more sales than the discount's size suggests to earn the same gross profit. The calculator below works it out from your own price, cost and sales.
Seller's discount calculator
The margin after a discount, and the extra units you need to sell for the same gross profit.
Extra units needed
+100.00%
Discounted price: 50 × (1 - 20%) = 40.
Profit per unit: 20 before, 10 after (40 - 30).
Margin: 40.00% before, 25.00% after.
Extra units needed: 20 ÷ 10 - 1 = 100.00% more units to earn the same gross profit.
Today: 100 units × 20 = 2,000 of gross profit. At 40 you need 200 units to match it.
Formula
profit per unit after = full price * (1 - discount) - cost
extra units needed = profit per unit before / profit per unit after - 1How many more sales does a discount need?
A product that sells for 50 and costs 30 makes 20 a unit, a 40% margin. At 20% off it sells for 40 and makes 10, a 25% margin. To earn the same 2,000 of gross profit as 100 full-price units, it has to sell 200: 100% more. The table runs the same product at other discounts.
| Discount | Price | Profit per unit | Margin | Extra units needed | Units for the same gross profit |
|---|---|---|---|---|---|
| 5% | 47.50 | 17.50 | 36.84% | +14.29% | 115 |
| 10% | 45.00 | 15.00 | 33.33% | +33.33% | 134 |
| 15% | 42.50 | 12.50 | 29.41% | +60.00% | 160 |
| 20% | 40.00 | 10.00 | 25.00% | +100.00% | 200 |
| 25% | 37.50 | 7.50 | 20.00% | +166.67% | 267 |
| 30% | 35.00 | 5.00 | 14.29% | +300.00% | 400 |
| 40% | 30.00 | 0.00 | 0.00% | Not possible | No number is enough |
The cost here is the direct cost of one unit. Payment fees, shipping and the cost of winning the order often stay the same at a lower price too, so the real hurdle can be higher; the profit calculator counts those costs. For the margin on its own, use the margin calculator; to set a price from a cost, the markup calculator.
Should you discount, or fix the page first?
A discount buys extra sales by giving up part of the profit on every sale, including the ones that would have happened at full price. A higher conversion rate at the full price has no such cost: every extra order keeps the whole margin. Before a sale, it is worth asking why visitors who want the product are not buying.
- Find your hurdle. Use the seller's calculator to see how many more units the discount needs.
- Measure your baseline. The conversion rate calculator gives today's rate on the page you would discount.
- Check the page. Unclear pricing, weak trust signals and a slow or awkward checkout lose buyers whatever the price.
- Test before you commit. Run the discount as a test against full price and judge it on gross profit per visitor, not on orders alone. The guide to psychology in pricing covers how prices and discounts are presented.
Convertica's free CRO audit runs eight checks on a page, scores each out of 100 and gives you three fixes, so you can see what might be holding sales back before you give away margin.
Related calculators
A discount changes one price. These calculators cover what it does to the rest of the sum.
See all free tools and how they fit together.
Discount calculator FAQ
How does a discount calculator work?
A discount calculator multiplies the original price by the percent off to get the amount saved, then subtracts it from the original price to get the sale price. 20% off 80 is 80 × 0.2 = 16 saved and a sale price of 64. Given two prices instead, it divides the difference by the original price to get the percent off.
How do I calculate 20% off?
Multiply the price by 0.8, or multiply it by 0.2 and subtract the result. 20% off 50 is 50 × 0.8 = 40, a saving of 10. The same works for any percent: 30% off means multiplying by 0.7, 15% off by 0.85.
How do I calculate the discount percentage between two prices?
Subtract the sale price from the original price, divide by the original price and multiply by 100. A price cut from 80 to 60 is (80 - 60) / 80 × 100 = 25% off. Always divide by the original price, not the sale price: 20 / 60 would give 33.33%, which is not the discount.
How do I find the original price before a discount?
Divide the sale price by 1 minus the discount as a decimal. A sale price of 60 after 25% off was 60 / 0.75 = 80. Adding 25% back onto 60 gives 75, which is wrong, because the 25% was taken off the larger original price.
Is 20% off and then 10% off the same as 30% off?
No. Discounts applied one after another multiply, they do not add. 20% off and then 10% off leaves 0.8 × 0.9 = 72% of the price, a combined discount of 28%. On a price of 100 that is 72, against 70 for a single 30% discount. The order of the two discounts makes no difference.
What is 40% off $120?
40% off $120 is $72. The amount saved is $120 × 0.40 = $48, and $120 - $48 = $72. In one step, multiply $120 by 0.60, the share of the price you still pay.
How much more do I need to sell to make up for a discount?
Divide the profit per unit before the discount by the profit per unit after it, and subtract 1. A product that sells for 50 and costs 30 makes 20; at 20% off it makes 10, so it needs 20 / 10 - 1 = 100% more units for the same gross profit. If the discount wipes out the profit, no volume makes it up.
Does a discount reduce my margin by the same percentage?
No. A discount comes off the price while the cost stays the same, so the margin falls by more than the discount. On a product that sells for 50 and costs 30, the margin is 40%. At 20% off, the price is 40, the profit 10 and the margin 25%.
