Greatest Common Factor Chart Collection

Choose from a wide variety of free printable greatest common factor (GCF) charts in different sizes.

What is a Greatest Common Factor (GCF)?

The greatest common factor (GCF) of two or more integers is the largest positive integer that divides each of them evenly, with no remainder.

For example, the GCF of 12 and 18 is 6 since the factors of 12 are 1, 2, 3, 4, 6, and 12 and the factors of 18 are 1, 2, 3, 6, 9, and 18. 12 and 18 have 4 common factors (1, 2, 3, and 6). The greatest of these common factors is 6.

Other names for Greatest Common Factor include Greatest Common Divisor (GCD) and Highest Common Factor (HCF.)

If two numbers have a GCF of 1, they are known as relatively prime numbers or coprime numbers.

Using a GCF Chart

While you can find the greatest common factor of two numbers using the strategy above of listing all of the factors of each number, it can be quite time consuming and tedious.

To use the GCF chart, find the cell that corresponds with the row of the first number and the column of the second number. For example, if you look at the 12th row and the 18th column, you will find the number 6 since the GCF of 12 and 18 is 6.