regular quadrilateral
(Redirected from Square (geometry))
A square and its diagonals
Drawing a square

A square is a shape with four equal sides and four corners that are all right angles (90 degrees). The diagonals of a square also cross at right angles. The angle between any diagonal and a side of a square is 45 degrees. A square has rotational symmetry of four. It has four lines of regular symmetry.

A square is a type of rectangle with all sides of equal length. However note that while a square is a type of rectangle, a rectangle does not necessarily need to be a square.

A square is also the 2-dimensional analogue of a cube.


If the length of side a is known:

Length of diagonal  

If the length of diagonal d is known:

Length of side  


  1. 1.0 1.1 "Square. Formulas and Properties of a Square". onlinemschool.com. Retrieved February 17, 2018.