W6x20 is a wide flange steel beam that is 6.2 in deep with a 6.02 in flange and weighs 20 lb/ft (29.8 kg/m). Its metric designation is W150x29.8. All values below come from the AISC Shapes Database v16.0.
W6x20 Dimensions
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Nominal weight | W | 20 lb/ft | 29.8 kg/m |
| Cross-sectional area | A | 5.87 in² | 3,790 mm² |
| Depth | d | 6.2 in | 157 mm |
| Flange width | bf | 6.02 in | 153 mm |
| Web thickness | tw | 0.26 in | 6.6 mm |
| Flange thickness | tf | 0.365 in | 9.27 mm |
| Distance to web toe of fillet (design) | kdes | 0.615 in | 15.6 mm |
| Distance to web toe of fillet (detailing) | kdet | 0.875 in | 22.2 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 | 3.5 in | 88.9 mm |
W6x20 Section Properties
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Moment of inertia, x-axis | Ix | 41.4 in⁴ | 17.2 ×10⁶ mm⁴ |
| Elastic section modulus, x-axis | Sx | 13.4 in³ | 220 ×10³ mm³ |
| Plastic section modulus, x-axis | Zx | 14.9 in³ | 246 ×10³ mm³ |
| Radius of gyration, x-axis | rx | 2.66 in | 67.6 mm |
| Moment of inertia, y-axis | Iy | 13.3 in⁴ | 5.54 ×10⁶ mm⁴ |
| Elastic section modulus, y-axis | Sy | 4.41 in³ | 72.3 ×10³ mm³ |
| Plastic section modulus, y-axis | Zy | 6.72 in³ | 110 ×10³ mm³ |
| Radius of gyration, y-axis | ry | 1.5 in | 38.1 mm |
| Torsional constant | J | 0.24 in⁴ | 99.9 ×10³ mm⁴ |
| Warping constant | Cw | 113 in⁶ | 30.3 ×10⁹ mm⁶ |
| Effective radius of gyration | rts | 1.7 in | 43.2 mm |
| Distance between flange centroids | ho | 5.84 in | 148 mm |
| Flange slenderness | bf/2tf | 8.25 | 8.25 |
| Web slenderness | h/tw | 19.1 | 19.1 |
W6x20 Weight Calculator
Enter a length to get the total weight of a W6x20 beam. A 20 ft length weighs 400 lb.
Uses the AISC nominal weight: 20 lb/ft (29.8 kg/m).
Beams Similar to W6x20
| Shape | Weight (lb/ft) | Depth (in) | Flange width (in) |
|---|---|---|---|
| W6x16 | 16 | 6.28 | 4.03 |
| W6x25 | 25 | 6.38 | 6.08 |
| W6x15 | 15 | 5.99 | 5.99 |
Compare all W shapes in the wide flange beam sizes chart.
W6x20 FAQ
What does W6x20 mean?
W means wide flange. The first number (6) is the nominal depth in inches, and the second number (20) is the weight in pounds per foot. The actual depth of W6x20 is 6.2 in. How to read steel beam sizes.
How much does a W6x20 beam weigh?
W6x20 weighs 20 lb per foot (29.8 kg per meter). A 20 ft beam weighs about 400 lb. Use the calculator above for any length.
What is the metric equivalent of W6x20?
The metric (SI) designation is W150x29.8: 157 mm deep with a 153 mm flange and 29.8 kg/m.
How far can a W6x20 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.