Percentage Calculator

Work out a percentage of a number, what percent one number is of another, and percentage change.

What is% of=

is what % of=

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How to use it

Fill in whichever line matches your question. Each line works on its own.

X% of Y multiplies Y by X ÷ 100.
A is what % of B divides A by B and multiplies by 100.
Percentage change is (new − old) ÷ old × 100. A negative answer is a decrease.

Is a 50% rise followed by a 50% fall back to the start?

No. 100 up 50% is 150, and 150 down 50% is 75. Each percentage applies to a different starting value.

What is the difference between percent and percentage points?

If a rate goes from 4% to 5%, it rose by 1 percentage point, but by 25 percent of its old value.