Surface Area Calculator
Surface area and volume of cylinders, cones, spheres and more.
About this tool
Choose a shape and enter its dimensions, plus an optional unit. The tool shows the total surface area, the lateral (side) area and base area where they apply, and the volume.
Surface area formulas
Surface area is the total area of a solid's outer faces: what you'd paint, wrap or cut from sheet material. For a cylinder of radius r and height h it's 2πr(r + h), made of the curved side 2πrh (a can's label) and two circular ends; r = 3, h = 5 gives 150.8 square units. A sphere has 4πr², exactly four times the area of its largest circle, so r = 2 gives 50.27. A cone is πr(r + s), using the slant height s = √(r² + h²), and a square pyramid is a² + 2as. Boxes are 2(lw + lh + wh), cubes 6a², triangular prisms twice the triangle's area (found from its three sides with Heron's formula) plus the perimeter times the length, and a torus (doughnut) 4π²Rr. The volume is shown too, so you can compare how much material a container uses with how much it holds. Honest limits: these are ideal shapes, so subtract the top for open containers and allow extra for overlaps and seams; the area comes out in the square of your unit. The volume calculator and the area calculator are related.
Frequently asked questions
What is the surface area of a cylinder?
2πr(r + h): the curved side 2πrh plus two circular ends of πr² each.
What is the surface area of a sphere?
4πr². A sphere of radius 2 has about 50.27 square units.
What is lateral surface area?
The area of the sides only, excluding the top and bottom faces.
How do I find the surface area of a cone?
πr(r + s), where s = √(r² + h²) is the slant height.
Is my data sent anywhere?
No. Everything is calculated in your browser, and nothing is stored or sent.