Circle Area & Circumference Calculator
Calculate circle area and circumference from radius, diameter, or circumference. Enter the known value and get instant, precise results.
Circle Area & Circumference Calculator
Related calculators
Back to Geometry CalculationsCone Volume
Compute cone volume from radius and height.
Cube Volume
Compute cube volume and related measurements from side length.
Cylinder Volume & Area
Compute cylinder volume and surface area from radius and height.
Irregular Polygon Area
Compute the area of an irregular polygon using the shoelace formula.
Pythagorean Theorem
Solve right triangles by finding the hypotenuse or a missing leg with a^2 + b^2 = c^2.
Understanding Circle Calculations: Formulas and Properties
A circle is a closed curve in geometry where all points are equidistant from a fixed center point. The fundamental properties of a circle include radius, diameter, area, and circumference.
Area represents the space enclosed by the circle and is calculated using A = π × r². Circumference is the perimeter of the circle, calculated as C = 2 × π × r. This calculator uses these fundamental formulas to compute other values from radius, diameter, or circumference.