Circle Calculator
Calculate area, circumference, radius and diameter of a circle.
Result
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Formulas
Durchmesser: d = 2 * r
Umfang: U = 2 * Pi * r = Pi * d
Fläche: A = Pi * r²
Note: These calculations are for informational purposes only and do not replace professional tax or financial advice. All information without guarantee.
Frequently Asked Questions
How do I calculate the area of a circle?
Area equals pi times radius squared (A = pi times r squared). With a radius of 5 cm, the area is approximately 78.54 square centimeters.
How do I calculate the circumference of a circle?
Circumference equals 2 times pi times radius (or pi times diameter). With a diameter of 10 cm, the circumference is approximately 31.42 cm.
What is the Circle Calculator?
The circle calculator computes circumference, area, diameter and radius of a circle from one known value.
How does the Circle Calculator work?
Enter the radius, diameter, circumference or area. The calculator computes all other values: circumference = 2 * pi * r, area = pi * r squared. Additionally, circular segment and sector are calculated.
Key Data and Facts
Circumference = 2 * pi * r = pi * d. Area = pi * r squared. Pi approx. 3.14159. Sector area = (angle / 360) * pi * r squared.
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