Calculate all circle properties — area, circumference, diameter and radius — from any single known value. Enter any one measurement and get all the others instantly.
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Diameter = 2 x radius. Circumference = pi x diameter = 2 x pi x radius.
Pi ≈ 3.14159265358979 — the ratio of any circle circumference to its diameter.
First find radius: circumference / (2 x pi). Then area = pi x radius squared.
A chord is a line between two points on the circle. An arc is part of the circumference. A sector is a pie-slice region.
Circumference is the specific term for a circle perimeter. Both measure total boundary length.
radius = square root of (area / pi). For area 50: radius = root of (50/3.14159) = 3.99 units.
A circle with radius 1 centred at the origin. Points on it are (cos theta, sin theta).
Room areas, wheel circumference, tank design, pipe cross-sections and road arc lengths.
