W6x12 is a wide flange steel beam that is 6.03 in deep with a 4 in flange and weighs 12 lb/ft (18 kg/m). Its metric designation is W150x18. All values below come from the AISC Shapes Database v16.0.
W6x12 Dimensions
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Nominal weight | W | 12 lb/ft | 18 kg/m |
| Cross-sectional area | A | 3.55 in² | 2,290 mm² |
| Depth | d | 6.03 in | 153 mm |
| Flange width | bf | 4 in | 102 mm |
| Web thickness | tw | 0.23 in | 5.84 mm |
| Flange thickness | tf | 0.28 in | 7.11 mm |
| Distance to web toe of fillet (design) | kdes | 0.53 in | 13.5 mm |
| Distance to web toe of fillet (detailing) | kdet | 0.75 in | 19.1 mm |
| Web center line to flange toe of fillet | k1 | 0.5625 in | 14.3 mm |
| Distance between web toes of fillets | T | 4.5 in | 114 mm |
| Workable gage (inner holes) | WGi | 2.25 in | 57.2 mm |
W6x12 Section Properties
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Moment of inertia, x-axis | Ix | 22.1 in⁴ | 9.2 ×10⁶ mm⁴ |
| Elastic section modulus, x-axis | Sx | 7.31 in³ | 120 ×10³ mm³ |
| Plastic section modulus, x-axis | Zx | 8.3 in³ | 136 ×10³ mm³ |
| Radius of gyration, x-axis | rx | 2.49 in | 63.2 mm |
| Moment of inertia, y-axis | Iy | 2.99 in⁴ | 1.24 ×10⁶ mm⁴ |
| Elastic section modulus, y-axis | Sy | 1.5 in³ | 24.6 ×10³ mm³ |
| Plastic section modulus, y-axis | Zy | 2.32 in³ | 38 ×10³ mm³ |
| Radius of gyration, y-axis | ry | 0.918 in | 23.3 mm |
| Torsional constant | J | 0.0903 in⁴ | 37.6 ×10³ mm⁴ |
| Warping constant | Cw | 24.7 in⁶ | 6.63 ×10⁹ mm⁶ |
| Effective radius of gyration | rts | 1.08 in | 27.4 mm |
| Distance between flange centroids | ho | 5.75 in | 146 mm |
| Flange slenderness | bf/2tf | 7.14 | 7.14 |
| Web slenderness | h/tw | 21.6 | 21.6 |
W6x12 Weight Calculator
Enter a length to get the total weight of a W6x12 beam. A 20 ft length weighs 240 lb.
Uses the AISC nominal weight: 12 lb/ft (18 kg/m).
Beams Similar to W6x12
| Shape | Weight (lb/ft) | Depth (in) | Flange width (in) |
|---|---|---|---|
| W6x15 | 15 | 5.99 | 5.99 |
| W6x9 | 9 | 5.9 | 3.94 |
| W6x8.5 | 8.5 | 5.83 | 3.94 |
See every W6 size in the W6 beam sizes chart, or compare all shapes in the wide flange beam sizes chart. Working in millimetres? W6x12 is listed as W150x18 in the metric wide flange beam sizes chart.
W6x12 FAQ
What does W6x12 mean?
W means wide flange. The first number (6) is the nominal depth in inches, and the second number (12) is the weight in pounds per foot. The actual depth of W6x12 is 6.03 in. How to read steel beam sizes.
How much does a W6x12 beam weigh?
W6x12 weighs 12 lb per foot (18 kg per meter). A 20 ft beam weighs about 240 lb. Use the calculator above for any length.
What is the metric equivalent of W6x12?
The metric (SI) designation is W150x18: 153 mm deep with a 102 mm flange and 18 kg/m.
How far can a W6x12 beam span?
Span depends on the load, support conditions, deflection limits and local building code, so it cannot be read from a size table. A licensed structural engineer must size any beam that carries a load.
Source: AISC Shapes Database v16.0, consistent with the AISC Steel Construction Manual, 16th Edition. Last updated: September 2026.
This page is reference information only and is not engineering advice. Do not use it for a specific design without verification by a licensed engineer or architect. Full disclaimer.