Regular Pentagon (5 sides) — free printable diagram

How many sides does a pentagon have?

A pentagon is a five-sided shape — a polygon with 5 sides and 5 corners. A regular pentagon has 5 equal sides and 5 equal angles of 108°.

Sides

5

Vertices (corners)

5

Interior angles add up to

540°

Each interior angle (regular)

108°

Each exterior angle (regular)

72°

Diagonals

5

Lines of symmetry (regular)

5

Also called

five-sided figure, five-sided polygon

• The interior angles of any pentagon add up to (5 − 2) × 180° = 540°.
• A regular pentagon has every angle the same, so each one measures 540° ÷ 5 = 108°.
• A pentagon has 5 diagonals — 5 × (5 − 3) ÷ 2.