Circle Calculator

Comprehensive circle calculations

Enter Radius
Calculate all circle properties from radius
Results
Diameter
0.00 units
Circumference
0.00 units
Area
0.00 sq units
Circle Formulas Reference
Basic Formulas:
• Diameter = 2 × radius
• Circumference = 2 × π × radius
• Area = π × radius²
Derived Formulas:
• Radius = diameter ÷ 2
• Radius = circumference ÷ (2π)
• Radius = √(area ÷ π)