Steel Beam Preliminary Sizing Calculator
Estimate minimum elastic section modulus from bending and minimum second moment of area from a simply supported UDL deflection check before selecting a real steel section.
Required section modulus Z
606061 mm³
Required second moment I
101250000 mm⁴
Deflection limit
16.67 mm
This calculator does not choose a code-compliant steel section. The selected member must also satisfy shear, lateral-torsional buckling, local buckling, section classification, web bearing, vibration, connections, fire/corrosion requirements and the applicable design code.
Equations used
Elastic bending estimate: Zrequired = M / σ. Simply supported UDL deflection: δ = 5wL⁴/(384EI), rearranged to estimate Irequired for the chosen serviceability limit.