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Percentage Calculator

Find X% of Y, work out what percent one number is of another, or calculate percent change between two values.

Result
10

How it works

This covers three common percentage questions with three formulas: X% of Y is (X ÷ 100) × Y. X as a percentage of Y is (X ÷ Y) × 100. Percent change from X to Y is ((Y − X) ÷ |X|) × 100, using the absolute value of the starting number so the sign of the result always reflects an increase or decrease correctly.

FAQ

Why does percent change use the absolute value of X?

Taking |X| in the denominator keeps the result's sign meaningful (positive for an increase, negative for a decrease) even when the starting value X is itself negative — a plain (Y−X)/X would flip the sign in that case.

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