# Radius of a circle Calculator | Given Area,circumference

## Circle Calculator

## Circle papramters

## How to use the online Circle calculator

You can use our online calculator for circle to find various paramters such as Area, Circumference/ perimeter, Diamter, Radius for any given circle

For each calculation you will need to input the base paramter depending on your selected calculation. Use the dropdown selector to choose the type of calculation e.g Calculate Area from Diamter

Once you have entered the base parameter e.g Radius, Circumference, Area or Diameter, hit the calculate Button to compute

**Commonly Used Symbols and their Meaning**

- r = radius
- d = diameter
- C = circumference
- A = area
- π = pi = 3.1415926535898
- √ = square root

## Find the Diameter of a circle calculator

Diameter of a circle is any straight line through the center of a circle and touches any two points on the circle. Determining the length of the diameter is a classical problem in plane geometry.

The diameter of a circle is related to its circumference and area according to the following formulas.

C= \pi d Or A= \pi \frac{d^2}{4}

From the above formula, it is possible to work out the value of the diameter given the area or the radius.

## Calculate diameter from circumference calculator

Calculating the diameter given the area is straight forward since the relationship between the circumference and the diameter is linear. All that is required is to make the diameter the subject of the formula as follows.

Since C= \pi d d=\frac {c}{pi}

## Find diameter from circumference calculator

To calculate the diameter given the circumference we use the formular:-

d=\frac {c}{\pi}

Or Diameter equals circumference/ perimeter divide by PI (3.14)

Our online calculator is a unique calculator that lets you find the diameter from the circumference. Further, the calculator shows you all the steps including the relation within the formula. To Calculate a diameter from circumference with a calculator, simply input the circumference value in the input field provided, and click on the calculate button to proceed.

## Finding diameter from Area with an online calculator

Our online calculator for finding diameter lets you calculate the diameter or radius from area. Given any circle, it is possible to work out its diameter from area or perimeter.

The radius of the circle is related to its area through the following formula.

A= \pi r^2
r = \sqrt { \frac{A}{\pi} }

Since d is twice the radius,

\implies \class{mt-space-3} d = 2r
d = 2\sqrt {a}{pi}

## Convert area into diameter and radius calculator

To calculate the diameter or radius given the area, we use the formular:-

r=\sqrt \left\frac {A}{\pi}\right

and

d=2\times\left\sqrt \left\frac {A}{pi}\right\riht

Or Diameter equals 2 times square root of Area divided by pi (3.14)

Our online calculator lets compute the value of radius or diameter from the area of a circle. The calculator is easy to use and can be used for any circle or units. Note that while using the online calculator, the values obtained are independent of the units applied.