Calculate percentages easily. Choose your calculation type below.
What is X% of Y?
What is X increased/decreased by Y%?
What is the % change from X to Y?
X is what percent of Y?
Result:
Understanding Percent Calculations
Percentages are a fundamental concept in mathematics, representing a fraction of 100. The "%" symbol signifies "per hundred." Percentages are widely used in finance, statistics, retail, and everyday life to express proportions, changes, discounts, taxes, and more.
The Math Behind Percentages
The core idea is to convert a percentage into a decimal or fraction for calculation. To convert a percentage to a decimal, divide by 100 (e.g., 25% = 25/100 = 0.25). To convert a decimal back to a percentage, multiply by 100 (e.g., 0.75 = 0.75 * 100 = 75%).
Common Percent Calculation Scenarios
Calculating a Percentage of a Number: To find X% of Y, you multiply Y by the decimal form of X. (X / 100) * Y.
Percentage Increase or Decrease: To increase or decrease a number Y by X%, you first calculate X% of Y and then add or subtract that value from Y. Y +/- ( (X / 100) * Y ), which can be simplified to Y * (1 +/- (X / 100)).
Calculating Percentage Change: To find the percentage change from an initial value X to a final value Y, use the formula: ( (Y - X) / X ) * 100. A positive result indicates an increase, while a negative result indicates a decrease.
Determining What Percentage One Number Is of Another: To find what percentage X is of Y, use the formula: (X / Y) * 100.
Calculator Usage
This tool simplifies these calculations. Select the type of calculation you need from the dropdown menu. The input fields will adjust accordingly. Enter your values, and the calculator will provide the precise result.
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case "percentOf":
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