Math

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Cube Volume, Area & Diagonal Calculator.

Calculate a cube's volume, surface area, and space diagonal from its edge.

On-device calculationNo signup
01

Set your values

Results update as you type.

volume: 125

volume

0.00000000
surfaceArea: 150

surfaceArea

0.00000000
spaceDiagonal: 8.66025404

spaceDiagonal

0.00000000

Results update automatically as you type.

Calculate a cube's volume, surface area, and space diagonal from its edge.

Use Cases

Packaging and Shipping

Determine the volume and surface area of cubic boxes to estimate shipping costs or material needed for wrapping.

Example: A box with edge 0.5 m has volume 0.125 m³ and surface area 1.5 m².

Architecture and Design

Calculate the space diagonal to ensure cubic structures fit in given spaces or to plan diagonal bracing.

Example: A cube with edge 4 m has a space diagonal of about 6.93 m.

Frequently Asked Questions

How do I calculate the volume of a cube?
Enter the edge length into the calculator. The volume is computed as edge length cubed (V = a³). For example, if the edge is 3 units, the volume is 27 cubic units.
What is the surface area of a cube?
The surface area is the total area of all six faces. It is calculated as 6 times the edge length squared (A = 6a²). For an edge of 2 units, the surface area is 24 square units.
What is the space diagonal of a cube?
The space diagonal is the longest diagonal connecting opposite vertices. It is calculated as edge length times the square root of 3 (d = a√3). For an edge of 1 unit, the diagonal is approximately 1.732 units.

Tips & Common Mistakes

Tips

  • Ensure the edge length is in the same unit for all calculations. The calculator uses the unit you enter consistently.
  • For quick mental checks, remember volume = a³, surface area = 6a², and diagonal = a√3.
  • If you have the volume and need the edge, take the cube root of the volume to find the edge length.

Common Mistakes to Avoid

  • Confusing surface area with volume: surface area is in square units, volume in cubic units.
  • Forgetting to multiply by 6 when calculating surface area, or forgetting to cube the edge for volume.
  • Using the edge length in different units (e.g., mixing cm and m) without conversion, leading to incorrect results.

Last updated: August 13, 2026