Image: Wikimedia Commons

circumference

Perimeter of a circle or ellipse

EntityQ843905

Subclass of: distance
, arc length
, perimeter

Overview

From Wikipedia, the free encyclopedia · Read full article · Text CC BY-SA 4.0

In geometry, the circumference is the perimeter of a circle or ellipse. The circumference is the arc length of the circle, as if it were opened up and straightened out to a line segment. More generally, the perimeter is the curve length around any closed figure. Circumference may also refer to the circle itself, that is, the locus corresponding to the edge of a disk. The circumference of a sphere is the circumference, or length, of any one of its great circles.

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All data

33 statements · 12% with external sources · numbers in brackets are citations

Different from: Umfang criterion used: descriptive page and disambiguation page have to be in different items
ISQ dimension: \mathsf{L}
Quantity symbol (LaTeX): C
In defining formula: C symbol represents: circumference
d symbol represents: diameter
r symbol represents: radius
\pi symbol represents: pi
\tau symbol represents: tau
Defining formula: C=\pi\cdot{d}=2\pi\cdot{r}=\tau\cdot{r}

On other databases

19 identifiers linking circumference across the web's reference databases

Data quality

statements

12%

externally sourced

Source last edited September 9, 2026. AIDB refreshes this page daily.

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AIDB. (2026). circumference (Q843905). Retrieved from https://aidb.si/e/circumference-Q843905