In geometry, the circumference (from Latin circumferēns 'carrying around, circling') is the perimeter of a circle or ellipse. The circumference is the arc length of the circle, as if it were opened up and …

Use this free circumference calculator to find the area, circumference and diameter of a circle.

Aug 3, 2023 · The circumference of a circle is the distance around the boundary of the circle. It is the same as calculating the perimeter of any polygon such as triangle, square, and rectangle.

Use this calculator to easily calculate the circumference of a circle, given its radius in any metric: mm, cm, meters, km, inches, feet, yards, miles, etc. If you know the diameter, first divide it by two to get …

This calculator computes the values of typical circle parameters such as radius, diameter, circumference, and area, using various common units of measurement.

The formula for circumference is based on the constant π (pi), which is an irrational number approximately equal to 3.14159. π is the ratio of the circumference to the diameter of any circle.

Circumference may be defined by some as the distance around the outside of an arbitrary closed object (sometimes restricted to a closed curved object). However, the term perimeter is used for this …

Dec 1, 2025 · In the work, the term "circumference" is used to mean the perimeter of a circle. However, some authors allow "circumference" to refer more generally to the distance or arc length around an …

The circumference of the circle is the length of its boundary. Explore and learn to calculate the circumference of a circle, with concepts, definitions, formulas, solved examples, and practice problems.

You sometimes see the word 'circumference' to mean the curved line that goes around the circle. Other times it means the length of that line, as in "the circumference is 2.11cm".