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Circumference of a Circle

The circumference of a circle is the distance once around it, equal to two pi times the radius (equivalently pi times the diameter). Pi is the fixed ratio of circumference to diameter, the same for every circle, which is why the formula holds at any size. This gives the total boundary length that any fraction of a full turn is measured against.

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How to Calculate the Circumference of a Circle

The circumference of a circle is defined by its proportional relationship to either its diameter or radius through constant pi (π). This geometric principle establishes that the linear distance aroun…