In geometry, an icosahedron is a polyhedron with 20 faces. The name comes from Greek εἴκοσι, meaning “twenty”, and ἕδρα, meaning “seat”. The plural can be either “icosahedra” or “icosahedrons”.
Length of edge (a): 1.00
Volume: 5×(3+√5)/12 × a³ = 2.18
Surface area: 5×√3 × a² = 8.66
Number of vertices: 12
Number of faces: 20
Number of edges: 30
Side shape: Triangle
Shapes with similar faces: Octahedron, Tetrahedron, Pentagonal pyramid, Triangular prism, Square pyramid, Hexagonal pyramid
