Find the greatest common factor (and least common multiple) of a list of numbers. Enter them separated by commas.
Usage Tip
To add fractions, the LCM of the denominators is the least common denominator; to reduce one, divide top and bottom by the GCF.
LCM is found from the same pairs.
The least common multiple is the smallest number all values divide into, used to add fractions.
Non-integer or non-positive entries are ignored.
Both the GCF and the LCM are shown.
The greatest common factor of a list of numbers is the largest number that divides all of them with no remainder. For 24 and 36 it is 12. It is also called the greatest common divisor or highest common factor.
The GCF is used to simplify fractions: divide the top and bottom by their GCF and the fraction is in lowest terms. It also helps when cutting material into the largest equal pieces or arranging items in identical groups with nothing left over. Two numbers with a GCF of 1 are said to be coprime. The calculator also shows the least common multiple, which is the product divided by the GCF for two numbers.