About Percentage Calculator
A percentage is a part expressed per hundred. This calculator takes two numbers, X and Y, and returns four results: X percent of Y (X ÷ 100 × Y), X as a percentage of Y (X ÷ Y × 100), Y increased by X percent (Y × (1 + X ÷ 100)), and Y decreased by X percent (Y × (1 − X ÷ 100)). The second result is undefined when Y is zero.
How to use Percentage Calculator
- Fill in "X" and "Y".
- The result appears below and updates as you type.
- Copy the result with the copy button, or download it as a file where that is offered.
Questions about Percentage Calculator
How do I calculate a percentage of a number?
Divide the percentage by 100 and multiply by the number. For example, 15% of 200 is 15 ÷ 100 × 200 = 30. Enter 15 as X and 200 as Y to see it in the first row.
Why does a 20% increase followed by a 20% decrease not return the original value?
The decrease applies to the larger, increased value. 100 raised by 20% is 120, and 20% of 120 is 24, so you end at 96 instead of 100.
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