Steel Beam Sizes / AISC / S-Shapes / S12x40.8
S12x40.8 Dimensions, Weight and Section Properties
AISC American standard beams · v16.0
S12x40.8: 12 in depth, 5.25 in flange width, 40.8 lb/ft weight. View the full dimensions and properties in imperial and metric units below.
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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
Compare weight neighbors, another Ix option, 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%)
Another Iₓ option 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