How do I type a repeating decimal?

Put the repeating digits in brackets: 0.3(3) is 0.333… and 0.1(6) is 0.1666…, which convert to 1/3 and 1/6.

Why is the answer always in lowest terms?

The result is divided by the greatest common divisor of numerator and denominator, and the sign is moved to the numerator.

Are big numbers supported?

Yes. Arithmetic uses BigInt internally, so even numerators with dozens of digits stay exact.

Can the denominator be 0?

No — a fraction with denominator 0 is undefined, and the tool will tell you so.

½Fraction Calculator - Add, Subtract, Multiply, Divide and Simplify

Do fraction arithmetic without the paperwork: enter two fractions and an operator for an automatically reduced answer, simplify a fraction to lowest terms, turn a fraction into a decimal with the repeating part marked, or turn a decimal — including a repeating one — back into a fraction.

Free · No sign-up · Runs in your browserLast updated: 2026-10-26

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How to use Fraction Calculator

1Choose fraction math, simplify, fraction → decimal or decimal → fraction
2Type the numerator and denominator (and pick + − × ÷ for arithmetic)
3Read the answer in lowest terms, as a mixed number, a decimal and a percentage

FAQ

How do I type a repeating decimal?: Put the repeating digits in brackets: 0.3(3) is 0.333… and 0.1(6) is 0.1666…, which convert to 1/3 and 1/6.
Why is the answer always in lowest terms?: The result is divided by the greatest common divisor of numerator and denominator, and the sign is moved to the numerator.
Are big numbers supported?: Yes. Arithmetic uses BigInt internally, so even numerators with dozens of digits stay exact.
Can the denominator be 0?: No — a fraction with denominator 0 is undefined, and the tool will tell you so.