Standard sections
Pick a shape: you get the closed-form formulas, an instant result and the option to continue in the interactive editor.
Moment of inertia of a rectangular section
Enter the width and the height to get the moments of inertia, the area, the section moduli and the radii of gyration of a rectangular section.
Moment of inertia of a rectangular section with a hole
Outer contour minus inner: the properties of a hollow rectangular section follow by subtraction.
Moment of inertia of a circular section
For a circle both axial moments are equal and the polar moment is twice as large — the value used when checking shafts in torsion.
Moment of inertia of an annular section (tube)
A tube keeps nearly all the stiffness of a solid shaft at a fraction of the mass.
Moment of inertia of a right triangle
Enter the legs to get the area, the centroid position and the moments of inertia about the centroidal axes.
Moment of inertia of a triangle from three points
Enter the three vertices — the calculation uses the general polygon formula, so the orientation of the sides does not matter.