The perimeter of a rectangle is a fundamental concept in geometry that refers to the total length around the rectangle. Whether you're designing a garden, framing a picture, or coding a geometry calculator, understanding how to calculate the perimeter is essential. This guide will walk you through the formula, provide a diagram, and show practical examples — all centered around our free online tool, the Perimeter of a Rectangle Calculator.
A rectangle is a quadrilateral with four right angles (90°) and opposite sides that are equal in length. It has two dimensions: length (l) and Breadth (b). These two values determine the perimeter and area of the shape.
The perimeter (P) of a rectangle is calculated using this simple formula:
P = 2 × (Length + Breadth)
That means you add the length and Breadth together and then multiply the result by 2. This accounts for both pairs of equal sides.
P = 2 × (l + b)Where:
Instead of doing the math by hand, you can use our interactive tool below. Just enter the values of Length and Breadth in the input fields, and the calculator will instantly display the perimeter.
Launch the Perimeter of a Rectangle Calculator
Length = 12 cm
Breadth = 8 cm
Perimeter = 2 × (12 + 8) = 2 × 20 = 40 cm
Length = 5.5 meters
Breadth = 3.2 meters
Perimeter = 2 × (5.5 + 3.2) = 2 × 8.7 = 17.4 meters
Calculating the perimeter of a rectangle is important in many real-world situations:
Perimeter is expressed in linear units such as centimeters (cm), meters (m), inches (in), feet (ft), etc. The units must be the same for both length and breadth.
Yes, our Perimeter of a Rectangle Calculator accepts both whole numbers and decimals for precision.
The calculator will show an error. Length and Breadth must always be positive numbers.
Understanding how to calculate the perimeter of a rectangle is a key skill in geometry and many practical applications. With our easy-to-use Perimeter of a Rectangle Calculator, you can quickly get accurate results for any rectangle size. Try it today and simplify your calculations!