Circle Area & Sector Calculator

Calculate the area, circumference, arc length, and sector area of a circle using radius and central angle.

Inputs

Radius (r)

010,00,000

Central Angle (degrees)

0360

Calculation Results

Total Area

78.54

Circumference

31.42

Arc Length

7.85

Sector Area

19.63

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Formula & Mathematical Explanation

\displaystyle A = \pi r^2, \quad C = 2\pi r, \quad L = \frac{\theta}{360} \times 2\pi r

The circle's area is πr² and circumference is 2πr. The arc length (L) and sector area are proportional to the fraction of the circle covered by the central angle θ.