Moment of Inertia & Section Modulus
Compute moment of inertia I and section modulus W for rectangle, solid circle and hollow circle.
Inputs
Formula
Rect I=bh³/12, W=bh²/6; Circle I=πd⁴/64, W=πd³/32; Hollow I=π(do⁴−di⁴)/64
How to use
- Fill in Section shape, Width b / Outer dia. do, Height h / Inner dia. di in the Inputs section (watch the unit on each field).
- Click Calculate; the tool evaluates the formula shown above.
- Read Moment of inertia I, Section modulus W in the results area.
Formula notesSection modulus W = I/c. Rectangle W = b·h²/6, circle W = π d³/32, hollow W = π d³(1−k⁴)/32.