Calculating the area and the perimeter The perimeter is the length of the outline of a shape. Word Study Meets Math. Area measures the space inside a shape.
To find the perimeter of a rectangle or square you have to add the lengths of all the four sides.
Understand the true meaning of area. In the attribute table in Table Options select Add Field. The Instruction and How to use the calculator online to count the Area and Perimeter of Circle 1. X is in this case the length of the rectangle while y is the width of the rectangle.