A double discount happens when two discounts are applied one after another. For example, a product may be 20% off, then have an extra 10% off at checkout. The important point is that the second discount is usually applied to the already discounted price, not the original price.
Use the calculator to check your own numbers, then read the guide for formulas, examples, and common mistakes.
What Is a Double Discount?
A double discount means two discounts are applied in sequence.
For example, an item may first receive 20% off, then another 10% off.
This does not usually mean 30% off the original price. The second discount is normally calculated from the reduced price.
Why Double Discounts Are Not Simply Added
Two discounts should not usually be added together because each discount uses a different base.
If a product is 100, a 20% discount reduces it to 80.
A second 10% discount is then taken from 80, not from 100.
Double Discount Formula
The double discount formula is: final price = original price × (1 - first discount ÷ 100) × (1 - second discount ÷ 100).
This formula applies the first discount, then applies the second discount to the new price.
It works for two percentage discounts applied one after another.
Double Discount Example
Suppose the original price is 100. The first discount is 20%. The second discount is 10%.
After the first discount, the price is 80.
Then 10% off 80 is 8, so the final price is 72.
Effective Discount Percentage
In the example, the final price is 72, so the total saving is 28.
That means the effective discount is 28%, not 30%.
This is why double discounts should be calculated step by step.
Example With a Higher Price
Suppose the original price is 250, with 25% off and then an extra 15% off.
After 25% off, the price is 187.50.
After another 15% off, the final price is 159.38.
Double Discount vs Single Discount
A double discount can be compared with one equivalent discount, but it must be calculated from the final price.
The effective discount percentage shows the real total reduction from the original price.
For simpler percentage-off examples, read Discount Formula.
Business Impact of Double Discounts
Double discounts can reduce sale price quickly, which may reduce profit margin if costs stay the same.
A business should check whether the final discounted price still leaves enough profit.
For the margin side, read How Discounts Affect Profit Margin.
Use the Calculator
Use the Discount Calculator for a single discount calculation.
For a double discount, calculate the first discounted price, then enter that new price as the original price for the second discount.
This step-by-step method avoids the mistake of simply adding the two discount percentages.
Conclusion
To calculate a double discount, apply the first discount to the original price, then apply the second discount to the reduced price.
Double discounts are usually not the same as adding the two percentages together.
Related guides and tools
FAQs
Can I add two discounts together?
Usually no. Double discounts are normally applied one after another, so the second discount uses the reduced price.
What is 20% off plus another 10% off?
On a price of 100, 20% off gives 80, then 10% off gives 72. The effective discount is 28%.
How do I calculate double discount?
Multiply the original price by the remaining percentage after each discount.