Cube Surface Area Calculator
Enter the edge length to find the total surface area.
How to Calculate the Surface Area of a Cube
A cube is a three-dimensional solid object bounded by six square faces, facets, or sides, with three meeting at each vertex. Because every side of a cube is an identical square, finding the surface area is a straightforward mathematical process.
The total surface area of a cube represents the sum of the areas of all six faces. Since each face is a square with an area of side × side (a²), and there are six faces, the formula is simple and elegant.
The Cube Surface Area Formula
To find the surface area, use the following formula:
Where "a" is the length of one edge (or side) of the cube.
If you only need the Lateral Surface Area (the area of the four sides, excluding the top and bottom), the formula is:
Step-by-Step Calculation Guide
- Measure the Edge: Determine the length of one side of the cube. Since it's a cube, all edges are equal.
- Square the Length: Multiply the edge length by itself (a × a). This gives you the area of one face.
- Multiply by Six: Take that result and multiply it by 6 to account for all six faces of the cube.
- Add Units: Surface area is always expressed in square units (e.g., cm², in², m²).
Practical Example
Scenario: You have a cardboard box that is a perfect cube. Each edge measures 10 centimeters. How much wrapping paper is needed to cover it?
- Edge (a): 10 cm
- Calculation: 6 × (10 × 10)
- Step 1: 10² = 100
- Step 2: 100 × 6 = 600
- Result: 600 cm²
Common Cube Surface Area Reference Table
| Edge Length (a) | One Face Area (a²) | Total Surface Area (6a²) |
|---|---|---|
| 1 unit | 1 sq. unit | 6 sq. units |
| 2 units | 4 sq. units | 24 sq. units |
| 3 units | 9 sq. units | 54 sq. units |
| 5 units | 25 sq. units | 150 sq. units |
| 10 units | 100 sq. units | 600 sq. units |
Frequently Asked Questions
Q: What is the difference between volume and surface area?
A: Volume measures the space inside the cube (a³), while surface area measures the total space of the outside faces (6a²).
Q: Can I find the edge length if I know the surface area?
A: Yes! Divide the total surface area by 6, then take the square root of that number to find the edge length: a = √(SA / 6).
Q: Does this formula work for rectangular prisms?
A: No. A rectangular prism has sides of different lengths. For that, you use the formula: 2(lw + lh + wh), where l is length, w is width, and h is height.