The Area of a Circle equation (A = π•r²)CIRCLE PARTS computes the area of a circle.
INSTRUCTIONS: Choose units and enter the following:
Area of a Circle (A): The calculator computes the area (A) in square meters. However, this can be automatically converted to many other area units (e.g. square inches) via the pull-down menu.
A = π•r²
A circle is a simple shape in Euclidean geometry. It is the set of all points in a plane that are at a given distance from a given point, the center; equivalently it is the curve traced out by a point that moves so that its distance from a given point is constant. The distance between any of the points and the center is called the radius.
A circle is a simple closed curve which divides the plane into two regions: an interior and an exterior. In everyday use, the term "circle" may be used interchangeably to refer to either the boundary of the figure, or to the whole figure including its interior; in strict technical usage, the circle is the former and the latter is called a disk.
A circle may also be defined as a special in which the two foci are coincident and the eccentricity is 0, or the two-dimensional shape enclosing the most area per unit perimeter, using calculus of variations.