This free I-Beam and H-Beam Section Modulus Calculator helps you compute the bending strength of standard and custom I-beam profiles. Enter basic dimensions like flange height, web thickness, and flange width to get section modulus values around both X-X and Y-Y axes. Supports metric and imperial units.

Beam Section Elastic Modulus Calculator
Calculation Results
Moment of Inertia (Ixx): —cm⁴Moment of Inertia (Iyy): —cm⁴
Elastic Section Modulus (Sxx): —cm³
Elastic Section Modulus (Syy): —cm³
Cross-sectional Area (A): —cm²
Formulas according to your specification:
Ixx = H³b/12 + 2[h³B/12 + hB(H+h)²/4]
Iyy = b³H/12 + 2(B³h/12)
Sxx = 2Ixx/(H + 2h)
Syy = 2Iyy/B
A = H·b + 2·B·h
What is the Elastic Section Modulus of an I-Beam or H-Beam?
The elastic section modulus of a beam is a critical geometric property used to evaluate its resistance to bending. For I-beams and H-beams, it helps determine the maximum bending stress under applied loads.
Bending About the Strong Axis (X–X Axis):
This is the most common loading scenario, where the beam flanges resist bending:
Sx = Ix / ymax
Where:
Sx = Section modulus about the X–X axis
Ix = Moment of inertia about the X–X axis
ymax = Distance from the neutral axis to the outermost fiber
Bending About the Weak Axis (Y–Y Axis):
Bending about the vertical web is much less resistant:
Sy = Iy / xmax
Where:
Sy = Section modulus about the Y–Y axis
Iy = Moment of inertia about the Y–Y axis
xmax = Distance from the neutral axis to the extreme fiber in Y-direction
Application:
Section modulus is used in flexural design equations to calculate bending stress:
σ = M / S
Where:
σ = Maximum bending stress
M = Bending moment
S = Section modulus (mm³ or in³)
Use this calculator to find the section modulus of I-beams and H-beams about both X–X and Y–Y axes. Supports both metric and imperial units.
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Key Features
- 🔹 Dual Axis Output: Calculates Sxx (strong axis) and Syy (weak axis)
- 🔹 Flexible Unit Selection: Input in mm/inch, output in cm³/in³
- 🔹 Easy to Use: Just input four beam dimensions and get instant results
- 🔹 Responsive Design: Works smoothly on both desktop and mobile
- 🔹 Default Example Included: IPE 360 profile pre-filled for quick reference
How to Use
- Input the following values:
- H: Distance between flanges (inner height)
- B: Overall flange width
- h: Flange thickness
- b: Web thickness
- Select input and output units
- Click Calculate
- View calculated section modulus values for both axes below the button
Tip: You can change dimensions to simulate custom or standard I-beams.
✅ FAQ
- Q1: What is the section modulus used for? A: It indicates the beam’s ability to resist bending; higher values mean better bending strength.
- Q2: What’s the difference between Sx and Sy? A: Sx is about the major axis (strong axis), and Sy about the minor axis (weak axis).
- Q3: Can this calculator be used for custom I-beams? A: Yes, as long as you accurately input all dimensions.
- Q4: Is this tool suitable for aluminum or stainless steel beams? A: Yes, the calculator is geometry-based and applies to all materials.