How to Use the Cylinder Surface Area Calculator
A cylinder is a solid with two flat circular ends and a curved side connecting them. Its surface area adds together the areas of both circular ends and the rectangle formed by unrolling the side: surface area = 2πr² + 2πrh. Its volume is the area of the circular base times the height: volume = πr²h. Knowing just the radius (r) and height (h) is enough to get both values at once, precisely.
For example, a cylinder with radius 5cm and height 10cm has a surface area of 2π(5²) + 2π(5)(10) = 157.08 + 314.16 = 471.24cm², and a volume of π(5²)(10) = 785.4cm³. These calculations come up constantly in real life — estimating material for cylindrical cans, pipes, storage tanks, or barrels.
Both radius and height must be greater than 0, and they should share the same unit for an accurate result. If you only know the diameter, just divide it by 2 and enter that as the radius. The cylinder formulas are also the foundation for volume calculations involving cones and spheres, so it's worth understanding them together.
Frequently Asked Questions
Surface area = 2πr² + 2πrh — the two circular ends (2πr²) plus the unrolled side (2πrh).
Volume = πr²h — the area of the circular base (πr²) times the height (h).
Divide the diameter by 2 and enter that as the radius; the calculation works the same way.