Loading page
Surface area of 3D shapes.
The Surface Area Calculator finds the total area of the outer faces of a 3D solid. Choose a cube, box, sphere, cylinder or cone, enter its dimensions and it returns the surface area in square units.
Surface area matters whenever you need to cover, paint, wrap or coat an object, since it tells you exactly how much material the outside requires.
The cone and cylinder formulas include both the curved side and the flat circular ends.
Surface area is the total area of the outside faces (square units); volume is the space inside (cubic units).
The distance from the apex straight down the sloping side to the edge of the base, equal to √(r² + h²).
Yes — 2πr(r + h) covers the curved wall plus both circular caps. Drop the 2πr² term for an open tube.
For painting, wrapping, plating, heat-loss and material estimates — anything involving the outside of an object.