Find the circumference of a circle using the formula 2 x π x r. You need the value of π, or pi, and the radius of the circle. More »

To find the circumference of a circle, multiply the diameter by pi or double the radius times pi. Pi is an unchanging number that rounds off to 3.14. More »

The circumference of a circle is the distance around the outskirts of the circle. Knowing the radius of any circle allows one to calculate its circumference. More »

To calculate a circle's diameter from its circumference, one should divide the circumference by the constant pi, which is an irrational number approximately equal to 3.14159265358979. More »

The circumference of a circle is the distance around the outskirts of the circle. Knowing the radius of any circle allows one to calculate its circumference. More »

If the circumference or the area of a circle is known, pi can be used to find the diameter and the radius of that circle. Likewise, if the radius or diameter is known, pi can be used to find out the circumference or the ... More »

To find the arc of a circle, divide the angle subtended at the center of the arc by 360 degrees, then multiply the answer by the circumference of the circle. You need to know the value of pi and must have a protractor to... More »