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Complete Circle Calculator
Formula
Enter the radius and instantly get the diameter, circumference, and area of any circle.
All formulas use pi (approximately 3.14159), the ratio of circumference to diameter.
Common use cases:
- Determining circle properties for design
- Comparing circular objects by size
- Educational geometry practice
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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