Circle Formula Calculator
MathFind the circumference, diameter, and area of a circle from its radius, with the formulas shown.
Circumference
The distance around the circle
Diameter
20.0000
The distance across the circle through its center
Area
314.1593
The space enclosed by the circle
Formulas used
The formulas behind each result above Circumference = 2 x pi x r, Diameter = 2 x r, Area = pi x r^2
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Odeh Ahwal0people find this calculator helpful
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Calculator Stats
Creators
Odeh Ahwal0people find this calculator helpful
Views
Helpful
Saved
Embeds
Math calculators
Frequently Asked Questions
What are the three core circle formulas?
Circumference equals 2 times pi times the radius, diameter equals 2 times the radius, and area equals pi times the radius squared.
What do the circle formulas give for a 10 unit radius?
For a radius of 10, circumference is about 62.83, diameter is 20, and area is about 314.16 square units.
Why does every circle formula involve pi?
Pi is the fixed ratio between a circle circumference and its diameter, so it appears in every formula that relates a circle size to its boundary or area.
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