Percentage Calculator

Three modes to handle the most common percentage problems. Select a mode, enter your numbers, and get an instant answer with a full explanation.

How to Calculate a Percentage

A percentage is a number expressed as a fraction of 100. The word "percent" means "per hundred." To find what percentage one number is of another, divide the first number by the second and multiply by 100.

What is X% of Y?

To find X% of Y, convert the percentage to a decimal by dividing by 100, then multiply by Y. For example, 25% of 80 = (25 ÷ 100) × 80 = 0.25 × 80 = 20.

Percentage Change Formula

Percentage change = ((New Value − Old Value) ÷ |Old Value|) × 100. A positive result means an increase; a negative result means a decrease.

Common Percentage Examples

ProblemAnswer
10% of 20020
25% of 8020
50% of 15075
15% of 609
5 is what % of 20?25%
30 is what % of 120?25%
% change from 50 to 75+50%
% change from 100 to 80-20%

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