Perimeter Calculator

The perimeter is the total distance around the outside of a two-dimensional shape. It's a fundamental concept in geometry with practical applications in various fields, from construction and architecture to gardening and design. This calculator helps you quickly determine the perimeter for common shapes like squares, rectangles, circles, and triangles.

How to Calculate Perimeter

The method for calculating perimeter depends on the shape you are working with. Below, we'll explore the formulas for the most common geometric figures.

Square Perimeter Calculator

A square is a quadrilateral with four equal sides and four right angles. To find its perimeter, you simply multiply the length of one side by four.

Formula: Perimeter = 4 × Side Length

Side Length: units

Rectangle Perimeter Calculator

A rectangle is a quadrilateral with four right angles, where opposite sides are equal in length. Its perimeter is found by adding the lengths of all four sides, or more simply, by adding the length and width and then multiplying the sum by two.

Formula: Perimeter = 2 × (Length + Width)

Length: units
Width: units

Circle Circumference Calculator

For a circle, the perimeter is referred to as its circumference. The circumference is the distance around the circle. It can be calculated using the radius (distance from the center to any point on the circle) or the diameter (distance across the circle through its center).

Formula: Circumference = 2 × π × Radius (where π ≈ 3.14159)

Radius: units

Triangle Perimeter Calculator

A triangle is a polygon with three sides and three angles. To find the perimeter of any triangle, you simply add the lengths of its three sides.

Formula: Perimeter = Side 1 + Side 2 + Side 3

Side 1: units
Side 2: units
Side 3: units

Examples of Perimeter Calculation

Square Example:

Imagine you have a square garden plot with a side length of 5 meters. To find the perimeter:

Side Length = 5 meters
Perimeter = 4 × 5 = 20 meters

You would need 20 meters of fencing to enclose the garden.

Rectangle Example:

Consider a rectangular room that is 8 feet long and 6 feet wide. To calculate the perimeter for baseboards:

Length = 8 feet
Width = 6 feet
Perimeter = 2 × (8 + 6) = 2 × 14 = 28 feet

You would need 28 feet of baseboard material.

Circle Example:

If you have a circular swimming pool with a radius of 3.5 meters, and you want to know the distance around it:

Radius = 3.5 meters
Circumference = 2 × π × 3.5 ≈ 2 × 3.14159 × 3.5 ≈ 21.99 meters

The distance around the pool is approximately 21.99 meters.

Triangle Example:

Suppose you have a triangular piece of land with sides measuring 70 feet, 100 feet, and 120 feet. To find the total length of its boundary:

Side 1 = 70 feet
Side 2 = 100 feet
Side 3 = 120 feet
Perimeter = 70 + 100 + 120 = 290 feet

The total boundary length is 290 feet.

Conclusion

Understanding how to calculate perimeter is a valuable skill for many everyday tasks and professional applications. Whether you're planning a home improvement project, designing a landscape, or solving a math problem, these simple formulas and our calculator can help you find the distance around various shapes with ease.

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