The outside of a solid
The surface area of a solid is the total area of all its outside faces. It tells you how much paint, wrapping, tiles, sheet metal or coating you need to cover an object.
This calculator covers 14 solids, including the cube, box, sphere, cylinder, cone, pyramids, frustum, capsule, ellipsoid and torus. It shows the volume too, and converts the area to square metres, feet, yards (gaj), acres and hectares.
How it is calculated
Box: 2(lw + lh + wh)
Cylinder: 2π r (r + h)
Cone: π r (r + slant height)
Sphere: 4 π r²
Worked example
Surface areas with lengths in centimetres
- Sphere, r 5
- 314.16 cm²
- Cylinder, r 3 and h 8
- 207.35 cm²
- Box, 6 × 4 × 3
- 108 cm²
Total vs lateral surface area
- Total surface area includes every face, including the top and bottom.
- Lateral area counts only the sides, for example the curved part of a can, and is shown for cylinders and cones.
- For an open box or tank, subtract the area of the missing lid.