Circumference and Area of a Circle Calculator Online

Calculate Circumference and Area of Your Circle

units
Enter the radius of your circle (e.g., 5).

Unlock the secrets of circles! Our free Circumference and Area of a Circle Calculator makes finding these key measurements simple. Just input the radius and get instant, accurate results for geometry, math, and engineering tasks. Understand the role of Pi (π) and solve your circular problems with ease. Try it now!

Formula:

The formulas used for calculating the circumference and area of a circle are:

  • Circumference (C): C = 2πr or C = πd
  • Area (A): A = πr²

Where:

  • π (Pi) ≈ 3.14159
  • r represents the radius of the circle (distance from the center to any point on the edge).
  • d represents the diameter of the circle (distance across the circle through its center, d = 2r).

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