Surface Area Calculator
Calculate the surface area of various three-dimensional shapes with ease.
Enter Shape Dimensions
Table of Contents
What is Surface Area?
Surface area is the total area of all the surfaces of a three-dimensional object. It represents the sum of the areas of all the faces or surfaces that make up the object. Surface area is measured in square units such as square meters, square centimeters, square inches, or square feet.
Surface Area Formulas
Cube
SA = 6s²
where s is the length of one side
Box
SA = 2(lw + lh + wh)
where l is length, w is width, and h is height
Sphere
SA = 4πr²
where r is the radius
Cylinder
SA = 2πr² + 2πrh
where r is the radius and h is the height
Cone
SA = πr² + πrs
where r is the radius and s is the slant height
How to Calculate Surface Area
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1Identify the three-dimensional shape you're working with
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2Measure the required dimensions (length, width, height, radius, etc.)
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3Apply the appropriate formula for the shape
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4Calculate the surface area using the formula
Practical Examples
Cube Example
A cube has sides of 3 units each.
SA = 6s²
SA = 6 × 3²
SA = 54 square units
Box Example
A box has dimensions of 4 × 3 × 2 units.
SA = 2(lw + lh + wh)
SA = 2(4×3 + 4×2 + 3×2)
SA = 52 square units
Sphere Example
A sphere has a radius of 2 units.
SA = 4πr²
SA = 4π × 2²
SA ≈ 50.27 square units
Cylinder Example
A cylinder has a radius of 2 units and a height of 5 units.
SA = 2πr² + 2πrh
SA = 2π × 2² + 2π × 2 × 5
SA ≈ 87.96 square units
Cone Example
A cone has a radius of 3 units and a height of 4 units.
SA = πr² + πrs
SA = π × 3² + π × 3 × 5
SA ≈ 75.40 square units