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Percentage Converter

Convert between a percentage, a decimal, and a fraction, and see what X% of a number actually is.

Your numbers

%

The percentage you want converted.

Used for the "X% of Y" result below.

As a decimal

0.2500

As a simplified fraction
1/4
Result of X% of the number
50.00
The math behind it
  1. As a decimal

    25 ÷ 100equals0.25

  2. 25% of 200

    0.25 × 200equals50

Percentages, decimals, and fractions are three ways of writing the same value. This tool converts between them instantly and also calculates what a given percentage of any number actually comes out to, the calculation behind discounts, tips, interest rates, and commission.

How it works

To convert a percentage to a decimal, divide by 100: 25% becomes 0.25.

To express it as a fraction, that decimal is simplified using the greatest common divisor of the numerator and denominator, so 25% reduces to 1/4 rather than staying as 25/100.

To find "X% of Y," the decimal form is multiplied by the number you provide. For example, 25% of 200 is 0.25 × 200, which is 50.

A worked example

Entering 25% and 200 shows a decimal of 0.25, a simplified fraction of 1/4, and a result of 50, since 25% of 200 is 50.

Questions people ask

How do I convert a decimal back to a percentage?

Multiply the decimal by 100 and add a percent sign: 0.25 becomes 25%. Enter that percentage value into the calculator above to see the fraction and "of a number" results too.

Why isn't my fraction fully simplified?

The calculator simplifies using the greatest common divisor, so it should always return the lowest terms. If you entered a percentage with several decimal places (e.g. 33.333%), the fraction reflects that exact value rather than rounding to a "nicer" one like 1/3.

Can I use this for percentage increase or decrease?

This tool converts a percentage and finds "X% of Y." For a change from one value to another (percentage increase/decrease), you'd instead divide the difference by the original number. The Percentage Change Calculator does that for you.