STANDARD STEEL I-BEAM SIZES CHART


Standard Steel I-Beam Sizes Chart for sizes, dimensions and section properties of standard steel I beams (S shapes). S shapes are designated by the letter S followed by the nominal depth in inches and the weight in pounds per foot. Thus S12 × 50 designates an I-beam with a depth of 12 inches and a nominal weight of 50 pounds per foot.


Standard Steel I-Beam Sizes
Standard Steel I-Beam Sizes, Dimensions and Section Properties Chart
Desig-
nation
Nom.
Weight, lb/ft
Area,
A, in2
Depth,
d, in
Flange Web
Thickness
tw, in
Axis X-X Axis Y-Y
Width,
bf, in
Thick-
ness,
ttf, in
I,
in4
S,
in3
r,
in
I,
in4
S,
in3
r,
in
S24 x 121 121 35.6 24.50 8.050 1.090 0.800 3160 258 9.43 83.3 20.7 1.53
S24 x 106 106 31.2 24.50 7.870 1.090 0.620 2940 240 9.71 77.1 19.6 1.57
S24 x 100 100 29.3 24.00 7.245 0.870 0.745 2390 199 9.02 47.7 13.2 1.27
S24 x 90 90 26.5 24.00 7.125 0.870 0.625 2250 187 9.21 44.9 12.6 1.30
S24 x 80 80 23.5 24.00 7.000 0.870 0.500 2100 175 9.47 42.2 12.1 1.34
S20 x 96 96 28.2 20.30 7.200 0.920 0.800 1670 165 7.71 50.2 13.9 1.33
S20 x 86 86 25.3 20.30 7.060 0.920 0.660 1580 155 7.89 46.8 13.3 1.36
S20 x 75 75 22.0 20.00 6.385 0.795 0.635 1280 128 7.62 29.8 9.32 1.16
S20 x 66 66 19.4 20.00 6.255 0.795 0.505 1190 119 7.83 27.7 8.85 1.19
S18 x 70  70 20.6 18.00 6.251 0.691 0.711 926 103 6.71 24.1 7.72 1.08
S18 x 54.7   54.7 16.1 18.00 6.001 0.691 0.461 804 89.4 7.07 20.8 6.94 1.14
S15 x 50 50 14.7 15.00 5.640 0.622 0.550 486 64.8 5.75 15.7 5.57 1.03
S15 x 42.9 42.9 12.6 15.00 5.501 0.622 0.411 447 59.6 5.95 14.4 5.23 1.07
S12 x 50 50 14.7 12.00 5.477 0.659 0.687 305 50.8 4.55 15.7 5.74 1.03
S12 x 40.8 40.8 12.0 12.00 5.252 0.659 0.462 272 45.4 4.77 13.6 5.16 1.06
S12 x 35 35 10.3 12.00 5.078 0.544 0.428 229 38.2 4.72 9.87 3.89 0.980
S12 x 31.8 31.8 9.35 12.00 5.000 0.544 0.350 218 36.4 4.83 9.36 3.74 1.00
S10 x 35 35 10.3 10.00 4.944 0.491 0.594 147 29.4 3.78 8.36 3.38 0.901
S10 x 25.4 25.4 7.46 10.00 4.661 0.491 0.311 124 24.7 4.07 6.79 2.91 0.954
S8 x 23 23 6.77 8.00 4.171 0.426 0.441 64.9 16.2 3.10 4.31 2.07 0.798
S8 x 18.4 18.4 5.41 8.00 4.001 0.426 0.271 57.6 14.4 3.26 3.73 1.86 0.831
S7 x 20 20 5.88 7.00 3.860 0.392 0.450 42.4 12.1 2.69 3.17 1.64 0.734
S7 x 15.3 15.3 4.50 7.00 3.662 0.392 0.252 36.7 10.5 2.86 2.64 1.44 0.766
S6 x 17.25  17.25 5.07 6.00 3.565 0.359 0.465 26.3 8.77 2.28 2.31 1.30 0.675
S6 x 12.5 12.5 3.67 6.00 3.332 0.359 0.232 22.1 7.37 2.45 1.82 1.09 0.705
S5 x 14.75 14.75 4.34 5.00 3.284 0.326 0.494 15.2 6.09 1.87 1.67 1.01 0.620
S5 x 10 10 2.94 5.00 3.004 0.326 0.214 12.3 4.92 2.05 1.22 0.809 0.643
S4 x 9.5 9.5 2.79 4.00 2.796 0.293 0.326 6.79 3.39 1.56 0.903 0.646 0.569
S4 x 7.7 7.7 2.26 4.00 2.663 0.293 0.193 6.08 3.04 1.64 0.764 0.574 0.581
S3 x 7.5 7.5 2.21 3.00 2.509 0.260 0.349 2.93 1.95 1.15 0.586 0.468 0.516
S3 x 5.7 5.7 1.67 3.00 2.330 0.260 0.170 2.52 1.68 1.23 0.455 0.390 0.522

Symbols: I = moment of inertia; S = section modulus; r = radius of gyration;

Supplements:

Link Usage
American Standard Beam (S Shape) Sizes Calculator Calculator form of the standard steel I-Beam sizes chart.

Definitions:

Second Moment of Area: The capacity of a cross-section to resist bending.

Radius of Gyration (Area): The distance from an axis at which the area of a body may be assumed to be concentrated and the second moment area of this configuration equal to the second moment area of the actual body about the same axis.

Section Modulus: The moment of inertia of the area of the cross section of a structural member divided by the distance from the center of gravity to the farthest point of the section; a measure of the flexural strength of the beam.

Reference:

  • Oberg, E. , Jones ,F.D. , Horton H.L. , Ryffel H.H., (2016) . Machinery's Handbook . 30th edition.  Industrial Press Inc. pp 2614
  • A 6/A 6M - 05a , Standard Specification for General Requirements for Rolled Structural Steel Bars, Plates, Shapes, and Sheet Piling