Understanding how to find the **Greatest Common Factor (GCF)** is an essential math skill that helps students solve all kinds of problems, from simplifying fractions to working on division. If you’re in 5th grade or looking to brush up on your GCF skills, this tutorial is for you!

We’re going to break it down step-by-step, and once you’ve got the hang of it, I’ll give you some free **Greatest Common Factor (GCF) Worksheets** to practice with. You’ll also get answers to check your work and see how you’re doing. Let’s get started!

**What is the Greatest Common Factor?**

So, what is the **Greatest Common Factor (GCF)**? The GCF is the **largest number that can evenly divide two or more numbers**. That’s it! The biggest number goes into both numbers without leaving a remainder.

For example, let’s say we want to find the GCF of 12 and 18:

- The factors of 12 are: 1, 2, 3, 4, 6, 12
- The factors of 18 are: 1, 2, 3, 6, 9, 18

Looking at both lists, the largest factor that 12 and 18 have in common is **6**. So, the **GCF of 12 and 18 is 6**. Easy.

**Steps to Find the GCF (Greatest Common Factor)**

Here’s how you can find the GCF of any two numbers:

**Step 1: List all the factors of each number**

A factor is any number that divides into your original number evenly. Start by writing down the factors for both numbers.

**Step 2: Circle the common factors**

Next, compare the lists of factors. Circle or underline the numbers that appear in both lists. These are your common factors.

**Step 3: Pick the largest common factor**

The biggest number that appears in both lists is the **GCF**!

**Example: Finding the GCF of 24 and 36**

Let’s work through another example to make sure we’ve got it.

- Factors of 24: 1, 2, 3, 4, 6, 8, 12, 24
- Factors of 36: 1, 2, 3, 4, 6, 9, 12, 18, 36

**Common factors**: 1, 2, 3, 4, 6, 12

The largest common factor is **12**, so the **GCF of 24 and 36 is 12**.

**Why Is Finding the GCF Important?**

Finding the GCF isn’t just a skill you learn once and forget about. You’ll use it over and over in math, especially when you start working with fractions or more complex problems. Here’s how:

**Simplifying fractions**: If you’ve got a fraction like 18/24, you can use the GCF of 18 and 24 (which is 6) to simplify it. Divide both the numerator and denominator by 6, and you get the simplified fraction 3/4.**Word problems**: GCF also shows up in math word problems, especially ones that involve splitting things up evenly, like dividing a class into groups or sharing items equally.

**Time to Practice Download Free GCF Worksheets with Answers**

Now that you know how to find the GCF, it’s time to practice. I’ve put together a set of **free worksheets** that will help you get better at finding the GCF. These worksheets are perfect for 5th graders but can also be used by anyone who wants to master this skill.

**Click the links below to download and print the worksheets**:

**Download GCF Worksheet #1 (Basic Problems)**

This worksheet has simpler problems where you’ll practice finding the GCF of smaller numbers.