# Mass moment of inertia of a Circle

Calculates the mass moment of inertia of a Circle or a thin circular ring.

`I_z = m*r^2` (about central axis)

`I_x=I_y = 1/2*m*r^2` (about diameter)**Enter 'x' in the field to be calculated.**

Here are formulas to calcule the mass moment of inertia of a circle or thin circular ring.

Case of a rotation about the central axis (z-axis on above diagram),

`I_z = m * r^2`

Case of a rotation about a diameter (x-axis or y-axis on above diagram),

`I_x = I_y = 1/2*m * r^2`

m : mass of the circle (kg)

r : circle radius in meter (m)

## See also

Mass moment of inertia Calculators

Convert mass units

Convert distance units

Convert units of mass moment of inertia

Physics Calculators