Common Factor Calculator

What this calculator helps you do

Use this common factor calculator to find the shared factors between two or more whole numbers. It is helpful for simplifying fractions, comparing divisibility, and checking the first step in greatest common factor problems.

How common factors work

A common factor is a number that divides each input exactly. For example, the common factors of 18 and 24 are 1, 2, 3, and 6.

Worked example

If you compare 30 and 45, the factors of 30 are 1, 2, 3, 5, 6, 10, 15, and 30. The factors of 45 are 1, 3, 5, 9, 15, and 45. The shared factors are 1, 3, 5, and 15.

How to use the result

• Simplify fractions
• Find the greatest common factor
• Check number relationships quickly

Bottom line

This page gives you the shared factor list directly so you can move on to the next step faster.