Decimal to Fraction Converter
Convert decimal numbers to fractions and vice versa. Simplify fractions to lowest terms.
About this calculator
Turn a decimal such as 0.375 into the fraction 3/8, or turn a fraction into its decimal. The tool reduces the fraction to lowest terms and also handles a whole-number part when converting back.
Useful for measurements in inches, recipes, school maths and spotting that 0.125 is exactly one eighth.
How to use it
- Choose Decimal → Fraction or Fraction → Decimal.
- Enter the decimal, or the whole part, numerator and denominator.
- Press Convert.
Method
Write the decimal over a power of ten, 0.375 = 375/1000, then divide both by their greatest common divisor, 375/1000 = 3/8. To go back, divide the numerator by the denominator.
Worked example
Common decimals
| 0.5 | 1/2 |
| 0.25 | 1/4 |
| 0.375 | 3/8 |
| 0.125 | 1/8 |
| 0.2 | 1/5 |
| 0.3333… | 1/3 |
Tips and common mistakes
- Memorise eighths: 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875.
- Repeating decimals like 0.333… cannot be written exactly with a short decimal; enter a fraction instead.
- For inch measurements, round to the nearest 1/16 or 1/32.
- Percentages convert the same way: 37.5% is 0.375, or 3/8.
- Check by dividing back.
Frequently asked questions
How do I convert a decimal to a fraction?
Write it over a power of ten and simplify.
What is 0.75 as a fraction?
3/4.
What is 0.625 as a fraction?
5/8.
How do I convert a fraction to a decimal?
Divide the numerator by the denominator.
Why is 1/3 not exactly 0.333?
Its decimal repeats without end.
Does the tool simplify automatically?
Yes, to lowest terms.