Rectangle Perimeter Calculator – ProMathTools

Rectangle Perimeter

Our Rectangle Perimeter Calculator helps you quickly find the total distance around the outside of any rectangular shape. Just input the length and width, and we'll do the math for you!

Length

Enter the length of the rectangle.

Width

Enter the width of the rectangle.

How it works

Our Rectangle Perimeter Calculator helps you quickly find the total distance around the outside of any rectangular shape. Just input the length and width, and we'll do the math for you!

The Formula

Perimeter = 2 × (Length + Width)

Worked Example

Calculating a Garden's Perimeter
Imagine you have a rectangular garden that is 15 feet long and 8 feet wide. To find its perimeter, you'd add the length and width (15 + 8 = 23) and then multiply by 2. So, 2 × 23 = 46 feet. This means you'd need 46 feet of fencing to enclose your garden.

Tips, Assumptions & Limitations

Remember, the perimeter is the total distance around the outside of a shape.
For a square, the length and width are the same, so you only need one measurement!
Ensure all your measurements are in the same units before calculating.

FAQ

The perimeter of a rectangle is the total distance around its outer boundary. It's found by adding up the lengths of all four sides.

Since a square is a special type of rectangle where all four sides are equal, you can calculate its perimeter by multiplying the length of one side by four, or by using the rectangle formula with length and width being the same value.

A rectangle has two pairs of equal sides: two lengths and two widths. So, you add one length and one width, and then multiply that sum by two to account for all four sides.