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125 LearnersLast updated on December 11, 2025

The perimeter of a shape is the total length of its boundary. The perimeter of a circle, also known as the circumference, refers to the total distance around the circle. In this topic, we will learn about the perimeter of a circumference.
The perimeter of a circumference, or simply the circumference of a circle, is the total distance around the circle.
The formula for the circumference of a circle is ๐ถ = 2πr, where r is the radius of the circle.
For instance, if a circle has a radius of 5 units, then its circumference is C = 2π(5) = 10π units.
Let’s consider another example of a circle with a radius of 7 units.
So the circumference of the circle will be: ๐ถ = 2πr = 2π(7) = 14π units.
To find the circumference of a circle, we just need to apply the formula and multiply the radius by 2π. For instance, a given circle has a radius of 3 units.
Circumference = 2πr = 2π(3) = 6π units.
Example Problem on Perimeter of Circumference - To find the circumference of a circle, we use the formula, ๐ถ = 2πr.
For example, let’s say the radius is 4 cm. Now, the circumference = 2π(4) = 8π cm. Therefore, the circumference of the circle is 8π cm.


Learning some tips and tricks makes it easier for children to calculate the circumference of circles. Here are some tips and tricks given below:
Always remember that a circle's circumference is given by the formula, ๐ถ = 2πr, where r is the radius of the circle.
Calculating the circumference starts by determining the radius or diameter of the circle.
If you have the diameter, remember that the radius is half of it (r = d/2), and use the circumference formula.
When dealing with problems involving multiple circles, organize the given radii or diameters before calculating the circumference for each individually.
To avoid mistakes when calculating the circumference, ensure that the radius or diameter measurements are accurate and consistent, especially in practical applications like construction and design.
If given the diameter instead of the radius, you can calculate the circumference using the formula ๐ถ = πd, where d is the diameter.
Did you know that while working with the circumference of a circle, children might encounter some errors or difficulties? We have many solutions to resolve these problems.
Here are some given below:
A circular garden has a radius of 8 meters. Find the circumference of the garden.
The circumference of the garden is 16π meters.
Given the radius of the circular garden is 8 meters.
Use the circumference formula C = 2πr. C = 2π(8) = 16π.
Therefore, the circumference of the garden is 16π meters.
A round table has a diameter of 1.5 meters. Calculate the circumference of the table.
The circumference of the table is 1.5π meters.
Given the diameter of the table is 1.5 meters.
Use the circumference formula C = πd.
C = π(1.5) = 1.5π.
Therefore, the circumference of the table is 1.5π meters.
Find the circumference of a circle whose radius is 10 cm.
The circumference of the circle is 20π cm.
Using the formula for circumference C = 2πr:
C = 2π(10) = 20π.
Therefore, the circumference of the circle is 20π cm.
A circular track has a diameter of 200 meters. What is the circumference of the track?
The circumference of the track is 200π meters.
Given the diameter of the circular track is 200 meters.
Use the circumference formula C = πd.
C = π(200) = 200π.
Therefore, the circumference of the track is 200π meters.
Calculate the circumference of a circular pool with a radius of 6 feet.
The circumference of the pool is 12π feet.
Given the radius of the circular pool is 6 feet.
Use the circumference formula C = 2πr.
C = 2π(6) = 12π.
Therefore, the circumference of the pool is 12π feet.

Seyed Ali Fathima S a math expert with nearly 5 years of experience as a math teacher. From an engineer to a math teacher, shows her passion for math and teaching. She is a calculator queen, who loves tables and she turns tables to puzzles and songs.
: She has songs for each table which helps her to remember the tables






