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Percentage calculator

Every everyday percentage question, answered as you type.

What is % of ?

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is what percent of ?

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is % of what?

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Percentage change from to

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Percent error: measured , true value

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Questions people ask

How do I calculate a percentage of a number?

Divide the percent by 100 and multiply by the number. 15% of 240 is 0.15 × 240 = 36.

How do I work out a percentage increase?

Subtract the old value from the new one, divide by the old value and multiply by 100. From 80 to 100 is (100 − 80) ÷ 80 × 100 = 25%.

Why isn’t a 50% rise undone by a 50% fall?

Because the second percentage is taken from a bigger number. 100 up 50% is 150; 150 down 50% is 75.