Perimeter Calculator

Calculate the perimeter of different geometrical figures by entering the required values into the calculator. This perimeter calculator also shows formulas for each shape to make it easier to understand.

How to Find Perimeter Using the Calculator?

Follow the given steps to find the perimeter of any geometrical figure without doing the manual calculation.

• Select the shape from the dropdown (e.g., Rectangle).
• Enter the length and width values.
• Choose the unit if needed (ft, m, etc.)
• Click the Calculate button.
• View the perimeter result instantly below

What is the Perimeter?

The perimeter refers to the total boundary of a closed geometric figure. The term "perimeter" is derived from the Greek word “perimetros” (per means “around” and metron means “measure”). It is measured using the same units as the length of the boundary being described (meters, inches, feet, miles, etc.).

Perimeter Formula for Every Geometrical Figure

Every geometrical figure has a different formula for perimeter. Below are the formulas for calculating the perimeter of the most typical shapes.

Square Perimeter Formula

P = 4a

a = edge length

Rectangle Perimeter Formula

P = 2l + 2w

l = length
w = width

Triangle Perimeter Formula

P = a + b + c

a = edge a
b = edge b
c = edge c

If all of the sides are unknown, you can also use our triangle calculator to calculate the perimeter using interior angles.

Trapezoid Perimeter Formula

P = a + b + c + d

a = base a
b = base b
c = side c
d = side d

Rhombus Perimeter Formula

P = 4a

a = edge length

Parallelogram Perimeter Formula

P = 2a + 2b

a = side
b = base

Pentagon Perimeter Formula

P = 5a

a = edge length

Octagon Perimeter Formula

P = 8a

a = edge length

Hexagon Perimeter Formula

P = 6a

a = edge length

Regular Polygon Perimeter Formula

P = an

a = edge length
n = number of sides

Circle Perimeter Formula

P = 2πr

r = radius

Use our circumference calculator to find the area, diameter, or radius.

Ellipse Perimeter Formula

P≈π[3(a+b)−(3a+b)(a+3b)]P \approx \pi \left[3(a+b) - \sqrt{(3a+b)(a+3b)}\right]P≈π[3(a+b)−(3a+b)(a+3b)]

a = axis a
b = axis b

Segment Perimeter Formula

P = πrθ/180 + 2r × sin(θ/2)

r = radius
θ = angle in degrees

Sector Perimeter Formula

P = 2r + ((2θπr) ÷ 360)

r = radius
θ = angle in degrees

Applications of Perimeter Calculator

• Gardening and fencing: Quickly measure total perimeter length for planning borders in your garden, yard, or property.
• DIY activities: Calculate the required amount of materials for woodwork, framing, and other projects.
• Construction and civil engineering: Obtain exact measurements of perimeters for planning, outlining, and site works.
• Sewing and crafts: Get more accurate measurements of pattern edges and fabric for better precision and outcome.
• Time-saving feature: Obtain measurements instantly, reducing the likelihood of error.
• Home Decoration: Improve your measurements for projects like flooring, painting edges, or laying tiles.
• Use for Students & Professionals: Anyone who needs fast perimeter calculations will find this to be a useful tool.

Frequently Asked Questions

Are the circumference and perimeter the same?

No, perimeter applies to polygonal shapes, while circumference is for circular shapes.

How do you differentiate between area and perimeter?

Perimeter is the outer length in total, and area is expressed in square units (length multiplied by width).

What is the method to find the perimeter of all shapes?

Every geometrical figure has different formulas to calculate the perimeter. For a rectangle, it is 2(l + w), and for a square, it is 4 x side.

Can all shapes be calculated using this perimeter calculator?

Yes, it has the capability for a multitude of shapes, including rectangular shapes, squares, and other fundamental shapes.

Why do we use a perimeter calculator?

It is to simplify the work for you and do the calculations with fewer chances of making mistakes.

Why is it important to find the perimeter?

It is important in the determination of this measurement to plan borders of all types, be it the setting up of a fence or the building of a frame around any structure.