Is 0.999... really equal to 1?

Yes. The repeating decimal 0.999... and 1 are two ways of writing the same number. One quick argument: 1/3 = 0.333..., and three times that is 0.999..., while three times 1/3 is exactly 1.

What is an improper fraction?

It is a fraction whose numerator is equal to or larger than its denominator, such as 11/4. It represents a value of 1 or more and can be written as a mixed number, here 2 3/4. Improper fractions are usually easier to calculate with.

Should I use fractions or decimals?

Fractions keep exact values like 1/3 that decimals can only approximate, so they are better for exact work and for measuring tools marked in fractions. Decimals are easier to compare and to use with money, calculators and spreadsheets.

Fractions & Decimals calculators

Q: How do I know if a fraction will give a repeating decimal?

Reduce the fraction to lowest terms and look at the denominator's prime factors. If they are only 2s and 5s, the decimal terminates; any other prime factor produces a repeating decimal. For example, 7/20 terminates because 20 = 2 × 2 × 5, but 7/12 repeats because 12 includes a factor of 3.

These tools cover fraction arithmetic, mixed numbers and conversion between fractions and decimals, with the fractions displayed stacked the way they are written by hand. They simplify every result to lowest terms and identify repeating decimals so you can see exactly what a value is.

5 tools · Updated October 21, 2026

Showing 5 tools

<Compare Fractions CalculatorMore fractions & decimals toolsOrder 3/4, 5/8 and 2/35/8 < 2/3 < 3/4

½Fraction CalculatorFraction arithmetic3/4 + 2/317/12 = 1 5/12

0.5Fraction to Decimal ConverterFraction and decimal conversion5/6 as a decimal0.8(3)

1½Mixed Number CalculatorFraction arithmetic2 3/4 + 1 1/24 1/4

≈Rounding CalculatorMore fractions & decimals toolsRound 2.345 to 2 decimal places2.35

Which one do I need?

I want to add or subtract two fractions with different denominatorsFraction Calculator I need to multiply or divide fractions and get a simplified answerFraction Calculator I am working with mixed numbers like 2 3/8 and 1 1/4Mixed Number Calculator I want to turn a fraction into a decimal and see if it repeatsFraction to Decimal Converter I need the decimal value of an inch fraction for a measurementFraction to Decimal Converter

Common denominators and lowest terms

Fractions can only be added or subtracted once they share a denominator. The most efficient common denominator is the least common multiple of the two, so 1/6 + 1/4 becomes 2/12 + 3/12 = 5/12. Multiplication is simpler: multiply the numerators, multiply the denominators, then simplify.

A fraction is in lowest terms when the numerator and denominator share no factor other than 1. The Fraction Calculator divides both by their greatest common divisor automatically and shows each step, which makes it useful for checking homework rather than only getting the answer.

Mixed numbers in practice

Mixed numbers such as 2 3/8 are easier to read but harder to calculate with. The reliable method is to convert to an improper fraction (2 3/8 = 19/8), do the arithmetic, then convert back. The Mixed Number Calculator does this for you and returns the result in mixed form, which is how measurements and recipes are usually written.

Use the Mixed Number Calculator for carpentry, sewing and cooking, where quantities are naturally whole units plus a part. Use the Fraction Calculator when the inputs are plain fractions or when you want an improper fraction as the result.

Which fractions terminate and which repeat

A fraction in lowest terms has a terminating decimal only if its denominator has no prime factors other than 2 and 5. That is why 3/8 = 0.375 ends while 1/3 = 0.333... and 1/7 = 0.142857142857... repeat forever. The Fraction to Decimal Converter detects the repeating block and marks it, instead of cutting it off after a fixed number of digits.

Converting the other way is also possible. A terminating decimal becomes a fraction over a power of ten (0.375 = 375/1000 = 3/8), and a repeating decimal can always be written as an exact fraction, which is why 0.142857... is exactly 1/7. Keep the fraction form when you need an exact value for further calculation, and round the decimal only at the final step.

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