W18x50 is a wide flange steel beam that is 18 in deep with a 7.5 in flange and weighs 50 lb/ft (74 kg/m). Its metric designation is W460x74. All values below come from the AISC Shapes Database v16.0.
W18x50 Dimensions
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Nominal weight | W | 50 lb/ft | 74 kg/m |
| Cross-sectional area | A | 14.7 in² | 9,480 mm² |
| Depth | d | 18 in | 457 mm |
| Flange width | bf | 7.5 in | 191 mm |
| Web thickness | tw | 0.355 in | 9.02 mm |
| Flange thickness | tf | 0.57 in | 14.5 mm |
| Distance to web toe of fillet (design) | kdes | 0.972 in | 24.7 mm |
| Distance to web toe of fillet (detailing) | kdet | 1.25 in | 31.8 mm |
| Web center line to flange toe of fillet | k1 | 0.8125 in | 20.6 mm |
| Distance between web toes of fillets | T | 15.5 in | 394 mm |
| Workable gage (inner holes) | WGi | 3.5 in | 88.9 mm |
W18x50 Section Properties
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Moment of inertia, x-axis | Ix | 800 in⁴ | 333 ×10⁶ mm⁴ |
| Elastic section modulus, x-axis | Sx | 88.9 in³ | 1,460 ×10³ mm³ |
| Plastic section modulus, x-axis | Zx | 101 in³ | 1,660 ×10³ mm³ |
| Radius of gyration, x-axis | rx | 7.38 in | 187 mm |
| Moment of inertia, y-axis | Iy | 40.1 in⁴ | 16.7 ×10⁶ mm⁴ |
| Elastic section modulus, y-axis | Sy | 10.7 in³ | 175 ×10³ mm³ |
| Plastic section modulus, y-axis | Zy | 16.6 in³ | 272 ×10³ mm³ |
| Radius of gyration, y-axis | ry | 1.65 in | 41.9 mm |
| Torsional constant | J | 1.24 in⁴ | 516 ×10³ mm⁴ |
| Warping constant | Cw | 3,040 in⁶ | 816 ×10⁹ mm⁶ |
| Effective radius of gyration | rts | 1.98 in | 50.3 mm |
| Distance between flange centroids | ho | 17.4 in | 442 mm |
| Flange slenderness | bf/2tf | 6.57 | 6.57 |
| Web slenderness | h/tw | 45.2 | 45.2 |
W18x50 Weight Calculator
Enter a length to get the total weight of a W18x50 beam. A 20 ft length weighs 1,000 lb.
Uses the AISC nominal weight: 50 lb/ft (74 kg/m).
Beams Similar to W18x50
| Shape | Weight (lb/ft) | Depth (in) | Flange width (in) |
|---|---|---|---|
| W18x46 | 46 | 18.1 | 6.06 |
| W18x55 | 55 | 18.1 | 7.53 |
| W18x60 | 60 | 18.2 | 7.56 |
See every W18 size in the W18 beam sizes chart, or compare all shapes in the wide flange beam sizes chart.
W18x50 FAQ
What does W18x50 mean?
W means wide flange. The first number (18) is the nominal depth in inches, and the second number (50) is the weight in pounds per foot. The actual depth of W18x50 is 18 in. How to read steel beam sizes.
How much does a W18x50 beam weigh?
W18x50 weighs 50 lb per foot (74 kg per meter). A 20 ft beam weighs about 1,000 lb. Use the calculator above for any length.
What is the metric equivalent of W18x50?
The metric (SI) designation is W460x74: 457 mm deep with a 191 mm flange and 74 kg/m.
How far can a W18x50 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.