Circle Circumference Calculator

Calculate the circumference (perimeter) and area of a circle from radius or diameter.

How to Use This Calculator

  1. Enter your Shape.
  2. Enter your Radius.
  3. Click Calculate to see instant results with a step-by-step breakdown.
  4. Use the Share button to copy a link with your inputs pre-filled.

⚠️ Results are for informational purposes only. Always verify important calculations with a qualified professional.

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