You are able to find the perimeter of the rectangle by adding length and width and multiplying by two because the opposite sides of a rectangle are equal in length. How to find the perimeter of a rectangle ? What is the perimeter of a rectangle formula? Check out this perimeter of a rectangle calculator and quickly estimate the necessary parameters of a rectangle . Learn how to calculate the perimeter of a rectangle using the formula P = 2 (length + width). See solved examples, applications and practice questions on perimeter of rectangle . Calculate the perimeter of any rectangle using its length and width in any metric or imperial unit. Learn the formula, see examples and applications of rectangular geometry.