Moment of inertia or second moment of area is important for determining the strength of beams and columns of a structural system. It is also required to find slope and deflection of beams.

Instructions for using this Calculator

This moment of inertia calculator is developed to help calculation of area, centroid, moment of inertia, section modulus and radius of gyration for rectangular, circular, Angle, T , Channel and I sections of structural members.

(i) This calculator takes the origin "O" of reference axes at the intersection of the horizontal axis (o-p) coinciding with the lower-most edge of the section and vertical axis (o-q) coinciding with the extreme left edge of the section. All the distances should be entered in cm and you will get  the calculated values in terms of corresponding units of cm . If the distances are entered in inch the values would in the corresponding units in inch.

(ii) The position of centroid 'C" is calculated in terms of its coordinates with references to origin of axes "O".

(iii) The moment of inertia is calculated about the x-x axis and y-y axis passing through the centroid of the section.

(iv) In case of hollow rectangular or hollow circular sections, the section should be symmetric about both x-x and y-y axes.

(v) In case of I section and T section, the section should be symmetric about y-y axis.