# Percentage Calculator

This free percentage calculator will help you do the math easy, enter two values X and Y below and click the "Calculate" button.

## How to calculate the percentage

Percentage, fraction of a whole number expressed in hundredths. The term “percentage” is derived from the Latin per centum, meaning “per hundred,” so the term represents fractions with the denominator 100. Thus, 20 percent means 20/100. Usually represented by the symbol %, percentage computations are commonly used today in finance and industry to calculate interest rates, costs, prices, profits, and so on; by the government to determine taxation; and by scientists to evaluate data.

To find the percentage of a number—for example, 20 percent of 40—20 must be changed to a common fraction (20/100) or to a decimal (.20) and the figure multiplied by the whole (40); thus

20 ÷ 100 x 40 = 8; 20 x 4 = 8

To find the percentage of a number—for example, 20 percent of 40—20 must be changed to a common fraction (20/100) or to a decimal (.20) and the figure multiplied by the whole (40); thus

4 ÷ 16 = .25; or 25 percent

If it is known that a number such as 8 is 5 percent of the principal number, the principal is found by dividing 8 by .05 to yield 160.