Reciprocal Calculator

This reciprocal calculator is able to determine the reciprocal of any number (except 0, of course).

Clear
Result2/3in lowest terms
Mixed number2/3
Decimal0.66666667
Percentage66.666667%

Reducing to lowest terms

Original24/36
Greatest common divisor12
Divide both by 122/3
Numerator factors2^3 × 3
Denominator factors2^2 × 3^2

The method

divide both parts by their greatest common divisor

The rules in one place

  • Adding and subtracting needs a common denominator first. The lowest common denominator keeps the numbers smallest, but any common denominator works.
  • Multiplying needs no common denominator at all — multiply across the top and across the bottom.
  • Dividing means multiplying by the reciprocal: flip the second fraction and multiply.
  • Reducing divides top and bottom by their greatest common divisor. It never changes the value.

Why lowest terms matter

6/8 and 3/4 are the same number, but 3/4 is easier to compare, easier to check and conventional in an answer. Reducing also keeps later arithmetic small: multiplying unreduced fractions makes the numbers grow fast, and cancelling first avoids that.