Steel Beam Sizes / AISC / S-Shapes / S12x40.8
S12x40.8 Steel Beam Dimensions and Properties
AISC American standard beams · v16.0
Diagram, properties emphasis, and nearby alternatives use the selected unit system.
Section diagram
S12x40.8 dimensions
Not to scale. Dimensions shown for reference.
Section properties
Symbols match the steel section finder. Imperial and metric values are shown side by side.
| Property | Imperial | Metric |
|---|---|---|
| Weight | 40.80 lb/ft | 60.70 kg/m |
| Depth, d | 12.00 in | 305.00 mm |
| Flange width, bf | 5.25 in | 133.00 mm |
| tw | 0.462 in | 11.700 mm |
| tf | 0.659 in | 16.700 mm |
| Area | 11.90 in² | 7,680.00 mm² |
| Ix | 270.00 in⁴ | 112,000,000 mm⁴ |
| Iy | 13.50 in⁴ | 5,620,000 mm⁴ |
| Sx | 45.10 in³ | 739,000.00 mm³ |
| Sy | 5.13 in³ | 84,100.00 mm³ |
| Zx | 52.70 in³ | 864,000.00 mm³ |
| Zy | 8.86 in³ | 145,000.00 mm³ |
| rx | 4.76 in | 121.00 mm |
| ry | 1.06 in | 26.90 mm |
| J | 1.69 in⁴ | 703,000.00 mm⁴ |
| Cw | 433.00 in⁶ | 116,000,000,000 mm⁶ |
Alternatives
Useful nearby sections
Same-series weight neighbors, closest Ix, and a nearby depth series when available — with percent change versus S12x40.8.
Lighter in S12
S12x35
- Weight
- 35.0 lb/ft (-14%)
- Depth
- 12.00 in (0.0%)
- Ix
- 228.0 in⁴ (-16%)
Heavier in S12
S12x50
- Weight
- 50.0 lb/ft (+23%)
- Depth
- 12.00 in (0.0%)
- Ix
- 303.0 in⁴ (+12%)
Closest Iₓ in S12
S12x31.8
- Weight
- 31.8 lb/ft (-22%)
- Depth
- 12.00 in (0.0%)
- Ix
- 217.0 in⁴ (-20%)
Similar weight in S15
S15x42.9
- Weight
- 42.9 lb/ft (+5.1%)
- Depth
- 15.00 in (+25%)
- Ix
- 446.0 in⁴ (+65%)
Source: AISC Shapes Database v16.0 · Methodology