How to Calculate Surface Area of a Cylinder

🥫Need to paint a can, wrap a pipe, or solve a geometry problem? Learn the easy way to calculate a cylinder’s surface area!

The surface area of a cylinder is the total area of all the sides you can touch — that includes the two circular ends and the curved surface around the side.

If you know how tall the cylinder is and the size of the circle on top, you can calculate the whole thing in just a couple of steps.

🙋‍♀️ What Is a Cylinder?

A cylinder is a 3D shape with:

• Two identical circular bases
• One curved side that wraps around

Think of a soda can, water pipe, or battery — those are cylinders!

🧮 The Formula for Surface Area of a Cylinder

The total surface area (TSA) of a cylinder includes:

• The top and bottom circles
• The curved side

Here’s the full formula:

Surface Area = 2πr² + 2πrh

Where:

• r = radius of the circular base
• h = height of the cylinder
• π ≈ 3.1416

Breakdown:

• 2πr² = area of the top and bottom circles
• 2πrh = area of the curved side (also called the lateral surface)

📋 Real Example

Let’s say you have a cylinder with:

• Radius = 4 cm
• Height = 10 cm

Step 1: Area of the two circles

2πr² = 2 × 3.1416 × (4²) = 2 × 3.1416 × 16 = 100.53 cm²

Step 2: Area of the curved surface

2πrh = 2 × 3.1416 × 4 × 10 = 251.33 cm²

Step 3: Add them together

Total Surface Area = 100.53 + 251.33 = 351.86 cm²

✅ The surface area of the cylinder is about 351.86 cm²

🎯 When Do You Need to Calculate This?

• Painting or labeling cans
• Calculating material for wrapping or packaging
• Solving school geometry problems
• Engineering or plumbing applications

✅ Quick Tips

• Always measure in the same unit (cm, m, in)
• Double-check if you’re given diameter instead of radius (just divide it by 2)
• π (pi) can be rounded to 3.14 or 3.1416 for quick calculations