Surface Area Calculator – Surface Area Formulas

Find the surface area of a shape by entering the dimensions and selecting a unit of measurement.

Select a Shape:

Rectangular Prism

Cube

Sphere

Cylinder

Cone

Pyramid

Capsule

Cap

Surface Area Result:

 


How to Find Surface Area

Surface area SA is the measure of the area of the surface of a 3-dimensional geometric shape or object. Surface area is measured in square units, such as square inches or feet.

Surface area is equal to the area of each side of an object added together. For instance, the surface area of a cube is equal to the area of each of the six sides of the cube added up.

When calculating the surface area of a shape, it is important to take all measurements using the same unit of measure. If your measurements are in different units, convert each measurement to the unit you want the results in.

Use our length unit conversion calculators to convert your measurements to a consistent unit.

Of course, the easiest way to find surface area is to use a calculator like the one above, but you can also find it using a formula. Read on to learn how to do it yourself.

Surface Area Formulas

Find the surface area for common shapes using the formulas below.

Cube Surface Area Formula

SA = 6a2

a = edge a length

Diagram of a cube showing e = edge length

Rectangular Prism Surface Area Formula

SA = 2lw + 2lh + 2wh

l = length
w = width
h = height

Diagram of a rectangular prism showing l = length, w = width, and h = height

Sphere Surface Area Formula

SA = 4πr2

r = radius

Diagram of a sphere showing r = radius

Cylinder Surface Area Formula

SA = 2πr(r + h)

base surface area = 2πr2
lateral surface area = 2πrh

r = radius
h = height

Diagram of a cylinder showing r = radius and h = height

Cone Surface Area Formula

SA = πr(r + r2 + h2)

base surface area = πr2
lateral surface area = πrr2 + h2

r = radius
h = height

Diagram of a cone showing r = radius and h = height

Pyramid Surface Area Formula

SA = e2 + 2e(e ÷ 2)2 + h2

base surface area = e2
lateral surface area = 2e(e ÷ 2)2 + h2

e = edge length
h = height

Diagram of a pyramid showing e = edge length and h = height

Capsule Surface Area Formula

SA = 2πr(2r + h)

end surface area = 4πr2
lateral surface area = 2πrh

r = radius
h = height

Diagram of a capsule showing r = radius and h = height

Cap Surface Area Formula

SA = π(r2 + h2) + πr2

base surface area = πr2
top surface area = π(r2 + h2)

r = radius
h = height

Diagram of a cap showing r = radius and h = height

You’ll probably also find our area and volume calculators useful. We have formulas for many geometric shapes.