MATH

Percentage Calculator

Free · No sign-up

Find a percentage of a number, a part-to-whole percentage or a percentage change.

Your result

MATH

Enter your values and select calculate.

On this page How it works & practical examples

How to use the Percentage Calculator

Choose the operation before entering values because the same inputs mean different things in each mode. “A% of B” treats A as a percentage. “A is what % of B?” treats A as a part and B as the reference whole. Change mode compares a new number B with an original number A. A percentage-point difference is a different operation: subtracting 20% from 30% gives 10 percentage points.

The calculation

A% of B = A × B / 100; share = A/B × 100; change = (B − A)/|A| × 100

Worked example

20% of 150 is 30. In share mode, 30 out of 150 is 20%. In change mode, going from 150 to 180 is a 20% increase.

Assumptions and limits

A reference whole of zero has no defined percentage, and percentage change from zero cannot be represented by this formula. For negative starting values, change uses the absolute magnitude of the original value so that an upward movement has a positive sign. This convention should be stated when reporting such a result. Values are rounded for display.

Common questions

Can the result exceed 100%?

Yes. A part can be greater than the chosen reference value, and a number can grow by more than its original size.

Are percentage change and percentage points the same?

No. Going from 20% to 30% is a rise of 10 percentage points and a 50% relative increase.