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Percentage Calculator
Three common percentage calculations. Instant results as you type.
What is X% of Y?
Result
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X is what % of Y?
Result
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Percentage Change
Change
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How this was calculated
X% of Y: Result = (X / 100) * Y
X is what % of Y: Result = (X / Y) * 100
% Change: Result = ((New - Old) / |Old|) * 100
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Percentages express a number as a fraction of 100. They are used everywhere: discounts, tax calculations, tips, grade scores, financial returns, and engineering tolerances. This calculator handles the three most common percentage questions instantly. Built by Groundwork Analytics.