Circle Calculator

Free Online Solve area, diameter, and circumference, circle equations. The area of a circle calculator will compute the surface of a circle using a radius or a diameter. Enter the circle area, diameter, or circumference and it will solve for the other two.

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How to use this Circle Calculator Tool?

How to use Yttags's Circle Calculator?

  • Step 1: Select the Tool
Circle Calculator Step 1
  • Step 2: Enter Any Of One And Click On The Solve Other Button.
Circle Calculator Step 2
  • Step 3: Check Your Circle Calculator Result
Circle Calculator Step 3

Calculate the area, circumference, radius and diameter of circles. Find A, C, r and d of a circle. Given any 1 known variable of a circle, calculate the other 3 unknowns. Circle formulas and geometric shape of a circle.

Circle formulas

D = 2R
C = 2πR
A = πR2
R: Radius
D: Diameter
C: Circumference
A: Area
π: 3.14159

If you want to link to Circle Calculator page, please use the codes provided below!

Circle Calculator

FAQs for Circle Calculator

What is a Circle Calculator?
A Circle Calculator is a tool or software that helps calculate various properties of a circle, such as its circumference, area, radius, diameter, and sector area, based on user-inputted values or formulas.
What are the key features of a circle calculator?
The Circle Calculator ( is adept at computing essential metrics associated with circles. With a given radius, diameter, circumference, or area, it can determine the other three values effortlessly, removing the need for intricate manual math.
How to calculate the size of a circle?
The circumference of a circle can be calculated using either C=𝜋d or C=2𝜋r. We know that the diameter of the circle is 8 cm, and an approximation for pi is 3.14, so we can plug these values into the formula C=𝜋d. The formula becomes C=(3.14)(8), which simplifies to 25.12.
How many degrees are in a circle?
A full circle has 360 degrees, which means that 100% of the circle is 360 degrees.
Is degree a SI unit?
A degree (in full, a degree of arc, arc degree, or arcdegree), usually denoted by ° (the degree symbol), is a measurement of a plane angle in which one full rotation is 360 degrees. It is not an SI unit—the SI unit of angular measure is the radian—but it is mentioned in the SI brochure as an accepted unit.