How to Calculate a Ratio (Made Simple!)

Ever hear someone say “the ratio is 3 to 1” and wonder what that actually means?
Good news: ratios are easy once you know the basics—and they’re super useful in everyday life.

Let’s break it down step by step.

🙋 What Is a Ratio?

A ratio is a way to compare two or more numbers. It tells you how much of one thing there is compared to another.

It’s written like this:

• 3:2 (spoken as “3 to 2”)
• Or as a fraction: 3/2
• Or even in words: “3 parts of A for every 2 parts of B”

📘 Example

If there are 6 apples and 3 oranges, the ratio of apples to oranges is:

6:3

✏️ How to Simplify a Ratio

Just like fractions, you can simplify ratios by dividing both sides by the same number.

Example:

6:3 → divide both numbers by 3 → 2:1

So the simplified ratio is 2:1.
This means for every 2 apples, there’s 1 orange.

⚙️ How to Calculate a Ratio

Let’s say you’re given two numbers and you want to write the ratio.

Example:

A classroom has 12 boys and 8 girls.
What’s the ratio of boys to girls?

Step 1: Write the numbers in order:

12:8

Step 2: Simplify by dividing both by 4:

12 ÷ 4 = 3  
8 ÷ 4 = 2  

🎉 So the simplified ratio is:

3:2

🔁 Reversing the Ratio

Ratios change depending on order.

• Boys to girls = 3:2
• Girls to boys = 2:3

Always check what’s being asked!

🧮 Ratio Calculator

Use the tool below to calculate a ratio. Enter the two numbers and the tool will calculate a simplified ratio

🛠️ Real-Life Examples

• Cooking: 2 cups of water to 1 cup of rice = 2:1
• Maps: 1 inch to 10 miles = 1:10
• Budgeting: If you spend $4 on groceries for every $1 on snacks, your ratio is 4:1
• Classes: If 15 students and 5 teachers, the ratio is 3:1

✅ Quick Recap