“U-channel” is an everyday name for a steel channel: a web with two flanges on the same side, which looks like a U lying on its side. In the United States, structural steel channels are made to the AISC shape series, where they are called C shapes (American Standard channels) and MC shapes (miscellaneous channels).
U-Channel vs C-Channel
There is no separate AISC U-channel series. When a US supplier or drawing lists a hot-rolled U-channel, it normally means a C or MC shape, so you can use the C and MC tables for dimensions. Light-gauge U-channels bent from sheet metal are a different product with their own manufacturer tables, and are not covered here.
Standard U-Channel (C Shape) Sizes
| Shape | Weight (lb/ft) | Depth (in) | Flange width (in) | Web (in) | Flange (in) |
|---|---|---|---|---|---|
| C3x3.5 | 3.5 | 3 | 1.37 | 0.132 | 0.273 |
| C3x4.1 | 4.1 | 3 | 1.41 | 0.17 | 0.273 |
| C3x5 | 5 | 3 | 1.5 | 0.258 | 0.273 |
| C3x6 | 6 | 3 | 1.6 | 0.356 | 0.273 |
| C4x4.5 | 4.5 | 4 | 1.52 | 0.125 | 0.296 |
| C4x5.4 | 5.4 | 4 | 1.58 | 0.184 | 0.296 |
| C4x6.25 | 6.25 | 4 | 1.65 | 0.247 | 0.296 |
| C4x7.25 | 7.25 | 4 | 1.72 | 0.321 | 0.296 |
| C5x6.7 | 6.7 | 5 | 1.75 | 0.19 | 0.32 |
| C5x9 | 9 | 5 | 1.89 | 0.325 | 0.32 |
| C6x8.2 | 8.2 | 6 | 1.92 | 0.2 | 0.343 |
| C6x10.5 | 10.5 | 6 | 2.03 | 0.314 | 0.343 |
| C6x13 | 13 | 6 | 2.16 | 0.437 | 0.343 |
| C7x9.8 | 9.8 | 7 | 2.09 | 0.21 | 0.366 |
| C7x12.25 | 12.25 | 7 | 2.19 | 0.314 | 0.366 |
| C7x14.75 | 14.75 | 7 | 2.3 | 0.419 | 0.366 |
| C8x11.5 | 11.5 | 8 | 2.26 | 0.22 | 0.39 |
| C8x13.75 | 13.75 | 8 | 2.34 | 0.303 | 0.39 |
| C8x18.75 | 18.75 | 8 | 2.53 | 0.487 | 0.39 |
| C9x13.4 | 13.4 | 9 | 2.43 | 0.233 | 0.413 |
| C9x15 | 15 | 9 | 2.49 | 0.285 | 0.413 |
| C9x20 | 20 | 9 | 2.65 | 0.448 | 0.413 |
| C10x15.3 | 15.3 | 10 | 2.6 | 0.24 | 0.436 |
| C10x20 | 20 | 10 | 2.74 | 0.379 | 0.436 |
| C10x25 | 25 | 10 | 2.89 | 0.526 | 0.436 |
| C10x30 | 30 | 10 | 3.03 | 0.673 | 0.436 |
| C12x20.7 | 20.7 | 12 | 2.94 | 0.282 | 0.501 |
| C12x25 | 25 | 12 | 3.05 | 0.387 | 0.501 |
| C12x30 | 30 | 12 | 3.17 | 0.51 | 0.501 |
| C15x33.9 | 33.9 | 15 | 3.4 | 0.4 | 0.65 |
| C15x40 | 40 | 15 | 3.52 | 0.52 | 0.65 |
| C15x50 | 50 | 15 | 3.72 | 0.716 | 0.65 |
Full properties, including area, centroid and Ix, are in the C-channel sizes chart and the MC channel dimensions 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.