Circle area calculator, formulas, practical use.

Circle area and circumference calculations

The circle area calculator is designed for calculations of radius, diameter, circumference or area of a circle. For successful calculation, you need to know and enter into the calculator at least one of parameters. Then press send or enter to run calculations.

Circle parameters sketch:

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Circle calculator form:

Circle calculator variables and constants explanation:

r – radius
C – circumference
d – diameter
A – area
π– 3,1415926535
– unspecified values
– specified values
– calculated values

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The formula for circle
circumference calculation:

The formula for circle
area calculation:

Circle calculator use:

Circle calculation is used in many industries and in a huge number of calculations. This is at least some of them:

perimeter of a tree trunk, limb, twig, stem, pipe, tube, hose, duct, wire, rod, cord, thread, rope, tunnel, pillar
cross-sectional area of a tree trunk, limb, twig, stem, pipe, tube, hose, duct, wire, rod, cord, thread, rope, tunnel, pillar
partial calculations of geometric shapes like cilinder, cone, sphere, barrel, torus and other rotational shapes
school calculations