Calculation of the area of a circle by diameter

Enter the circle diameter in m

The area of the circle is:

0.00m2
0.00cm2
0.00mm2

Enter the area of the circle in m2:

The diameter of the circle is:

0.00m

How to find the area of a circle?

S = Pi* d2 / 4,

where Pi = 3.1415926535 is the mathematical constant;

d — is the diameter of the circle