Surface Area Calculator
Calculate the surface area of common 3D shapes. Select a shape, enter its dimensions, and find the total surface area instantly.
Your Result
Select a shape and enter its dimensions to calculate the surface area.
What is Surface Area?
Surface area is the total area that the surface of a three-dimensional object occupies. In simpler terms, it's the sum of the areas of all the faces or surfaces on the outside of a 3D shape. While 2D area measures a flat space (like a square on paper), surface area measures the outer surface of a solid object (like the wrapping paper needed for a box). It is a different concept from volume, which measures the space *inside* an object. You can calculate volume with our Volume Calculator.
Surface Area Formulas for Common 3D Shapes
Cube
A cube has 6 identical square faces. To find the surface area, you calculate the area of one face (side²) and multiply it by 6.
Sphere
A sphere is a perfectly round 3D object. Its surface area is four times the area of a great circle (a circle with the same radius as the sphere).
Cylinder
A cylinder has two circular bases and a curved side. The total surface area is the sum of the areas of the two bases and the lateral (side) area. The base area can be found with our Circle Calculator.
Cone
A cone has one circular base and a curved side that tapers to a point (apex). Its surface area calculation requires the slant height (l), which is the distance from the apex to a point on the edge of the base.
Rectangular Prism (Cuboid)
A rectangular prism has 6 rectangular faces. The surface area is the sum of the areas of all 6 faces (3 pairs of identical rectangles).
Pyramid (with a Rectangular Base)
A pyramid has a polygonal base and triangular faces that meet at an apex. The total surface area is the area of the base plus the areas of all the triangular faces.
Practical Applications of Surface Area
Calculating surface area is critical in many scientific, engineering, and commercial fields:
- Manufacturing & Packaging: Determining the amount of material needed to create a box, can, or container, which helps in managing costs.
- Chemistry & Physics: Surface area affects reaction rates and heat transfer. A substance with a larger surface area (like a powder vs. a solid block) will react faster.
- Construction & Painting: Estimating the amount of paint, siding, or other materials needed to cover the surfaces of a building.
- Biology: The high surface area of lungs and intestines is crucial for efficient absorption of oxygen and nutrients.
For more useful tools, explore our full suite of Math calculators.