Use the calculator on the right to calculate the properties of a rectangle.

Enter the two side lengths and the rest will be calculated.
For example, enter the two side lengths. The area, perimeter and diagonal lengths will be found.

Other ways to think about rectangles

A rectangle can be thought about in other ways:

A
square
is a special case of a rectangle where all four sides are the same length.
Adjust the rectangle above to create a square.

It is also a special case of a
parallelogram
but with extra limitation that the angles are fixed at 90°.
See Parallelogram definition and adjust the parallelogram to create a rectangle.