Surface Area Calculator

Find the surface area of a box, cylinder, sphere, cone, or pyramid from its dimensions. Calculates in your browser.

Use one unit throughout, the area comes out in that unit squared.

Surface area

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ShapeBox / cube

Show the math

Each shape sums the area of its faces:

sphere = 4 × π × r²

cylinder = 2 × π × r × (r + h)

cone = π × r × (r + √(r² + h²))

Cones and pyramids use the slant height, found from the radius (or half the base) and the vertical height. Keep every dimension in the same unit and the area comes out in that unit squared. All math runs locally in your browser.

What this does

The surface area calculator finds the total outside area of common 3D shapes (box, cylinder, sphere, cone, and square pyramid) from the dimensions you enter. The result is in square units of whatever unit you use.

How to use it

  1. Choose the shape.
  2. Enter the required dimensions.
  3. Read the surface area in square units.

How it works

Each shape sums the area of its faces. A cone and a pyramid use the slant height, found from the radius (or half-base) and the vertical height.

sphere = 4 × π × r²; cylinder = 2 × π × r × (r + h)

Understanding your result

Surface area is what you need for paint, wrapping, plating, or heat-loss estimates, as distinct from volume, which is the space inside. Keep every dimension in the same unit and the area comes out in that unit squared, feet give square feet, metres give square metres.

Example

A sphere with a 3 ft radius has a surface area of about 113.1 sq ft (4 × π × 3²).

Sources & methodology

Last updated .

Frequently asked questions

Which shapes are supported?

Box (and cube), cylinder, sphere, cone, and square pyramid. Choose the shape and enter the dimensions it needs.

What is the difference between surface area and volume?

Surface area is the total area of the outside faces (square units); volume is the space enclosed inside (cubic units). Use surface area for coating or wrapping a shape.

What units does it use?

Whatever unit you enter. Keep every dimension in the same unit and the surface area is that unit squared.

Is my data stored?

No. Everything is calculated locally in your browser.