📐 Math
Circle Calculator
Quickly calculate all properties of a circle (radius, diameter, circumference, and area) by providing just one known value.
⏳
Formula
d = 2r | C = 2πr | A = πr²r- Radius
d- Diameter
C- Circumference
A- Area
Example
Finding Properties from Circumference
A circle has a circumference of 31.4 units. Find the radius and area.
- Use C = 2πr to find radius: r = C / 2π.
- Calculate radius: 31.4 / (2 × 3.14159) ≈ 5.
- Calculate area using A = πr².
- Area: π × 5² = 25π ≈ 78.54.
- Result: Radius = 5, Area = 78.54.
Frequently Asked Questions
This calculator uses the highly precise double-precision floating-point representation of Pi provided by the JavaScript Math.PI constant, which is approximately 3.141592653589793.