Cylinder Lateral Surface Area Calculator
Find the lateral (side) surface area of a cylinder from its radius and height using LSA = 2πrh, plus the total surface area.
How it works
Lateral = 2π·r·h · Total = 2π·r·h + 2π·r² = 2π·r·(r + h)
The lateral surface of a cylinder is the curved side alone, without the two circular ends. If you unroll it, it becomes a rectangle whose width is the circumference 2πr and whose height is h, so its area is 2πrh. Adding the two circular caps (each π·r²) gives the total surface area — useful when you need only the label area (lateral) versus the whole material (total).
Worked example
For a radius of 4 and a height of 10, the lateral surface area is 2π·4·10 = 80π ≈ 251.3274 square units, and the total is 80π + 2·π·16 = 112π ≈ 351.8584 square units.
Sources: Cylinder — Wikipedia
Frequently asked questions
What is the difference between lateral and total surface area?
Lateral surface area is only the curved side of the cylinder; total surface area adds the areas of the two circular ends. Use lateral for a label wrapping around a can, and total for the full sheet of metal.
Why is the lateral surface 2πrh?
Unrolling the curved side gives a rectangle. Its width equals the base circumference 2πr and its height equals the cylinder’s height h, so the area is 2πr × h.
How do I get the total surface area?
Add the two circular caps to the lateral area: total = 2πrh + 2πr² = 2πr(r + h).
Related calculators
This calculator is for educational purposes. Double-check important results before acting on them.