Ratio to Fraction Calculator

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On this page is a ratio to fraction calculator. Enter your ratio in the form X:Y and the tool will rewrite it as a fraction X/Y in its simplest whole number fraction form.

The tool works whether ratios are comparing two numbers as proportions, or comparing a number to a whole.

Ratio to Fraction Calculator

Convert a Ratio to a Fraction

Ratios and fractions are very closely linked, to the degree that you can use them interchangeably.

By tradition, we use fractions when discussing some amount of a whole (for example, a fraction of a group), and use ratios to compare whole numbers.

Sometimes, we also use ratios to describe a part of a whole – a smaller set to full set ratio.

For example:

  • In a class, there are 7 boys and 11 girls
  • 7:11 boy to girl ratio
  • 7/18 of the whole class is boys
  • (Sometimes) 7:18 boy to student ratio

Mathematically, ratios and fractions are the 'same' number. However, what we describe using them differs.

This tool can work with either type of ratio. Our fraction to ratio calculator can work in the opposite direction.

Using the Ratio to Fraction Calculator

To use the ratio to fraction calculator, enter the ratio in the Ratio box in the top of the tool. Then you have two options:

  • Of a whole: The ratio is in the form of a subset:whole, for example the 7:18 boy to student ratio from the example above.
  • Comparing numbers: The ratio compares two numbers, for example the 7:11 boy to girl ratio from the example above.

Next, hit the Convert to Fraction button. Depending on your input, the tool will then crunch the numbers and deliver you a simplified fraction.

Some related tools:

Next, see our other calculators and tools.



PK started DQYDJ in 2009 to research and discuss finance and investing and help answer financial questions. He's expanded DQYDJ to build visualizations, calculators, and interactive tools.

PK lives in New Hampshire with his wife, kids, and dog.

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