3D shapes
Faces, edges & vertices
3D shapes are described by their faces (flat surfaces), edges (where faces meet) and vertices (corners).
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6 faces · 12 edges · 8 vertices
The three parts
• Face — a flat surface of the shape. • Edge — a straight line where two faces meet. • Vertex — a corner where edges meet (more than one = vertices).
Worked examples
Faces of a cube
- Count the flat square surfaces of a cube.
Answer: A cube has 6 faces.
Edges of a cube
- Count the straight lines where the faces meet.
Answer: A cube has 12 edges.
Vertices of a cube
- Count the corners where the edges meet.
Answer: A cube has 8 vertices.
Where you see this in real life
- A dice is a cube with 6 faces.
- A cereal box is a cuboid — 6 faces, 12 edges, 8 vertices.
- Describing boxes and blocks in design and packing.
Key words
- Face
- A flat surface of a 3D shape.
- Edge
- A straight line where two faces meet.
- Vertex
- A corner where edges meet (plural: vertices).