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Fractions conversion

Fraction Converter: Decimals, Percents & Mixed Numbers

Use one tool to change how a number is written without changing the amount it represents. See the equation, the simplest form, and a parent-friendly explanation.

Same amount

0.625 = 62.5% = 5/8

Different forms can point to the same amount. The conversion steps explain why.

  • Decimals to fractions
  • Percent to fraction
  • Mixed numbers
  • Simplest form
  • Fractional inches

Interactive tool

Choose how you want to rewrite the number

A conversion changes the way a number is written, not the amount it represents.

Try an example

Result

Decimal to fraction

0.625

= 625/1000

= 5/8

The filled length stays the same while the name of one part changes.
Decimal place-value unit625/1000
Simplest fraction unit5/8

Light blue is the original decimal fraction. Dark blue is the same length rewritten with larger equal parts.

Decimal conversion

How to convert a decimal to a fraction

0.625 = 625/1,000 = 5/8

The digits after the decimal point tell you the starting denominator. Three digits means thousandths, so 0.625 becomes 625/1,000 before it is simplified.

For parents: Ask: “What does 625 mean here: tenths, hundredths, or thousandths?”

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Percent conversion

How to convert a percent to a fraction

62.5% = 62.5/100 = 625/1,000 = 5/8

Percent means “per 100.” Write the value over 100, remove the decimal by multiplying the top and bottom by the same power of 10, then simplify.

For parents: Say: “The percent sign tells us the amount is being counted out of 100.”

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Mixed number conversion

How to turn a mixed number into a decimal

2 3/4 = 2 + 3 ÷ 4 = 2.75

Keep the whole number, then turn the fraction part into a decimal. A fraction such as 3/4 ends at 0.75, while a fraction such as 1/3 repeats.

For parents: Ask: “How many whole ones do we have before we look at the fractional part?”

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Same amount, two forms

Convert mixed numbers and improper fractions

2 3/4 = 11/4

To make an improper fraction, use the denominator. Two wholes are eight fourths; add three fourths to get eleven fourths. Reverse the process with division and a remainder.

For parents: Say: “The amount stays the same. We are only choosing one way to write the wholes and leftover parts.”

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Simplest form

How to simplify 8/12

8/12 ÷ 4/4 = 2/3

Find a number that divides both the numerator and denominator. Dividing both by the same factor changes the name of the fraction, not the amount it represents.

For parents: Ask: “What number can split both 8 and 12 into equal groups?”

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Measurement example

Fractional inches and millimeters

5/8 in = 15.875 mm

Fractional inches can convert exactly to millimeters. Going from millimeters back to a common ruler fraction can require rounding, so the tool shows both the exact inch fraction and the nearest 1/16, 1/32, or 1/64 inch.

For parents: Say: “The exact inch value and the nearest ruler mark are related, but they are not always the same number.”

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Words you can use at home

  • A conversion does not change the amount. It only changes the way we name the same amount.
  • Ask what one whole is divided into before choosing a denominator.
  • For measurements, explain that converting millimeters to a common ruler fraction is an estimate unless the exact fraction happens to match it.

Keep learning about fractions

Common questions

Fraction Converter FAQ

0.625 means 625 thousandths, or 625/1,000. Both numbers can be divided by 125, giving 5/8.