This I-beam sizes chart lists all 28 American Standard beams (S shapes) in the AISC Shapes Database v16.0. S beams have narrow, tapered flanges. In everyday use, “I-beam” often also means a wide flange (W) beam, which has wider, parallel flanges and is far more common today; see the wide flange beam sizes chart.
S-Beam Sizes (American Standard, Tapered Flange)
S shapes are the original American Standard beam, and the tapered flange is what sets them apart. The inside face of each flange slopes at about 16.7 percent, roughly 2 in 12, so the flange is noticeably thicker where it meets the web than it is at the tip. Every W shape, by contrast, is rolled with parallel flange faces.
That slope has practical consequences. A beam clamp, a bolted connection or a standard washer sits on an angled surface rather than a flat one, so tapered washers or a beveled filler are needed to seat hardware square. It also makes S shapes narrower for their depth than almost any W shape, which is why they turn up in monorails, trolley tracks and machine bases where a narrow flange is wanted, and rarely in modern building frames where W shapes are lighter for the same strength.
| Shape | Weight (lb/ft) | Area (in²) | Depth (in) | Flange width (in) | Web (in) | Flange (in) |
|---|---|---|---|---|---|---|
| S24x121 | 121 | 35.5 | 24.5 | 8.05 | 0.8 | 1.09 |
| S24x106 | 106 | 31.1 | 24.5 | 7.87 | 0.62 | 1.09 |
| S24x100 | 100 | 29.3 | 24 | 7.25 | 0.745 | 0.87 |
| S24x90 | 90 | 26.5 | 24 | 7.13 | 0.625 | 0.87 |
| S24x80 | 80 | 23.5 | 24 | 7 | 0.5 | 0.87 |
| S20x96 | 96 | 28.2 | 20.3 | 7.2 | 0.8 | 0.92 |
| S20x86 | 86 | 25.3 | 20.3 | 7.06 | 0.66 | 0.92 |
| S20x75 | 75 | 22 | 20 | 6.39 | 0.635 | 0.795 |
| S20x66 | 66 | 19.4 | 20 | 6.26 | 0.505 | 0.795 |
| S18x70 | 70 | 20.5 | 18 | 6.25 | 0.711 | 0.691 |
| S18x54.7 | 54.7 | 16 | 18 | 6 | 0.461 | 0.691 |
| S15x50 | 50 | 14.7 | 15 | 5.64 | 0.55 | 0.622 |
| S15x42.9 | 42.9 | 12.6 | 15 | 5.5 | 0.411 | 0.622 |
| S12x50 | 50 | 14.7 | 12 | 5.48 | 0.687 | 0.659 |
| S12x40.8 | 40.8 | 11.9 | 12 | 5.25 | 0.462 | 0.659 |
| S12x35 | 35 | 10.2 | 12 | 5.08 | 0.428 | 0.544 |
| S12x31.8 | 31.8 | 9.31 | 12 | 5 | 0.35 | 0.544 |
| S10x35 | 35 | 10.3 | 10 | 4.94 | 0.594 | 0.491 |
| S10x25.4 | 25.4 | 7.45 | 10 | 4.66 | 0.311 | 0.491 |
| S8x23 | 23 | 6.76 | 8 | 4.17 | 0.441 | 0.425 |
| S8x18.4 | 18.4 | 5.4 | 8 | 4 | 0.271 | 0.425 |
| S6x17.25 | 17.25 | 5.05 | 6 | 3.57 | 0.465 | 0.359 |
| S6x12.5 | 12.5 | 3.66 | 6 | 3.33 | 0.232 | 0.359 |
| S5x10 | 10 | 2.93 | 5 | 3 | 0.214 | 0.326 |
| S4x9.5 | 9.5 | 2.79 | 4 | 2.8 | 0.326 | 0.293 |
| S4x7.7 | 7.7 | 2.26 | 4 | 2.66 | 0.193 | 0.293 |
| S3x7.5 | 7.5 | 2.2 | 3 | 2.51 | 0.349 | 0.26 |
| S3x5.7 | 5.7 | 1.66 | 3 | 2.33 | 0.17 | 0.26 |
Common Wide Flange I-Beam Sizes
| Shape | Weight (lb/ft) | Depth (in) | Flange width (in) |
|---|---|---|---|
| W6x20 | 20 | 6.2 | 6.02 |
| W8x15 | 15 | 8.11 | 4.02 |
| W8x18 | 18 | 8.14 | 5.25 |
| W8x21 | 21 | 8.28 | 5.27 |
| W8x28 | 28 | 8.06 | 6.54 |
| W8x58 | 58 | 8.75 | 8.22 |
| W10x22 | 22 | 10.2 | 5.75 |
| W10x26 | 26 | 10.3 | 5.77 |
| W10x30 | 30 | 10.5 | 5.81 |
| W10x33 | 33 | 9.73 | 7.96 |
| W10x39 | 39 | 9.92 | 7.99 |
| W10x68 | 68 | 10.4 | 10.1 |
| W12x22 | 22 | 12.3 | 4.03 |
| W12x26 | 26 | 12.2 | 6.49 |
| W12x30 | 30 | 12.3 | 6.52 |
| W12x35 | 35 | 12.5 | 6.56 |
| W12x40 | 40 | 11.9 | 8.01 |
| W12x65 | 65 | 12.1 | 12 |
| W14x22 | 22 | 13.7 | 5 |
| W14x26 | 26 | 13.9 | 5.03 |
| W14x30 | 30 | 13.8 | 6.73 |
| W14x38 | 38 | 14.1 | 6.77 |
| W16x26 | 26 | 15.7 | 5.5 |
| W16x31 | 31 | 15.9 | 5.53 |
| W16x36 | 36 | 15.9 | 6.99 |
| W16x50 | 50 | 16.3 | 7.07 |
| W18x35 | 35 | 17.7 | 6 |
| W18x50 | 50 | 18 | 7.5 |
| W30x108 | 108 | 29.8 | 10.5 |
Learn the difference in H-beam vs I-beam and how to read steel beam sizes. To work out section properties for a custom profile, try the I-beam moment of inertia calculator. For lighter non-steel sections, see the aluminum I-beam sizes chart. To see how size relates to span and load for wide flange beams, see the steel beam span chart and the I-beam load capacity chart.
Source: AISC Shapes Database v16.0, consistent with the AISC Steel Construction Manual, 16th Edition. Last updated: September 2026. Reference information only, not engineering advice. Disclaimer.