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Cube Net Explorer

Move the slider to change the side length of the cube. Then use the button to open the cube into a flat net. This helps explain why a cube has 6 equal square faces and why its surface area is 6 × side × side.

Controls

Small 4 units Large
One face
16
Faces
6
Surface area
96
Surface area = 6 × 4² = 6 × 16 = 96 square units
What is surface area?
It is the total area covering the outside of a 3D shape.

See it happen

Faces Edges of the net Highlighted face

How to explain it

  1. A cube has 6 faces.
  2. Each face is a square.
  3. If the side length is s, then one face has area s × s.
  4. Since all 6 faces are the same, multiply by 6.
  5. So the formula is 6s².