Fraction calculator

Whole-number inputs use exact integer arithmetic and a greatest-common-divisor reduction. Numerators and nonzero denominators must be within ±1,000,000,000. A decimal marked ≈ is rounded. The picture shows the magnitude of the fractional part; sign and any whole part are written separately.

For addition or subtraction, use a common denominator. For multiplication, multiply numerators and denominators. For division, multiply by the reciprocal; dividing by a zero fraction is undefined.

1/3 + 1/6 = 2/6 + 1/6 = 3/6 = 1/2. Half of one whole is shaded in the example picture.