Circumference to Diameter Calculator

Q: What is the circumference of a 6-foot diameter circle?

18.8496 feet . To convert diameter to circumference : Take the diameter . Multiply it by the number pi (π) . In this case, the circumference equals: π × 6 ft = 18.8496 ft .

Q: How do I get diameter from circumference?

Divide the circumference value by the number pi (π), or use the formula d = c/π . That's how you find the diameter of a circle with its circumference.

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Luis Hoyos

Luis is a mechanical engineer who works at Omni Calculator as a content creator and researcher specializing in math and physics calculators with a focus on thermodynamics and classical mechanics. With a strong foundation in mechanical engineering, Luis is passionate about creating tools that simplify complex concepts and improve everyday life. Outside of work, Luis likes weightlifting and applying his engineering knowledge to optimize the thermal conditions of his home, all while caring for four beloved cats. See full profile

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Wojciech Sas, PhD

Wojciech Sas

PhD, Institute of Physics in Zagreb

Wojciech, PhD, is a physicist at the Institute of Physics in Zagreb, investigating materials under extreme conditions such as low temperatures and high pressures. He specializes in experimental work, including participation in Large-scale User Facilities such as synchrotrons. Wojciech uses his experience and knowledge to create calculators in physics, math, and statistics categories. In his free time, he likes swimming, playing board games, and looking for meteors while stargazing. See full profile

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The circumference to diameter calculator can help you solve the geometry problem of finding the diameter of a circle by inputting its circumference. This calculator works both ways, so you can also convert a diameter to a circumference.

Keep reading to learn more about:

The circumference to diameter formula.
How to calculate circumference from the diameter.
How to get diameter from the circumference.

The circumference to diameter formula

Diameter and circumference are lengths related to each other — the higher the diameter, the higher the circumference. The circumference to diameter formula connects these variables in a single equation:

d = c/π

where:

d stands for the diameter;
c stands for the circumference; and
π is the pi number.

If, on the other side, you're interested in how to calculate circumference from the diameter, you can solve for c in the above equation:

c = π × d

💡 Did you know?
As you can imagine from the above equations, the number π is a constant equal to the circumference-to-diameter ratio of a circle (π = c/d). If you divide the circumference by the diameter, independently of the size, it'll always be 3.14159265...

How to find circumference from diameter: an example

Let's look at an example. Suppose you want to find the circumference of a 5 cm diameter circle. These would be the steps to follow:

Use the appropriate equation, which, in this case, is the circumference to diameter formula:

c = πd
Input the diameter in the equation:

c = π × (5 cm) = 15.708 cm
That's it. Also, check your results using our circumference to diameter calculator. Input 5 cm in the diameter box. Your result should also be 15.708 cm.

FAQs

What is the circumference of a 6-foot diameter circle?

18.8496 feet. To convert diameter to circumference:

Take the diameter.
Multiply it by the number pi (π).
In this case, the circumference equals: π × 6 ft = 18.8496 ft.

How do I get diameter from circumference?

Divide the circumference value by the number pi (π), or use the formula d = c/π. That's how you find the diameter of a circle with its circumference.

The circumference to diameter formula

How to find circumference from diameter: an example

Other-circle related tools

What is the circumference of a 6-foot diameter circle?

How do I get diameter from circumference?