W18x86 is a wide flange steel beam that is 18.4 in deep with an 11.1 in flange and weighs 86 lb/ft (128 kg/m). Its metric designation is W460x128. All values below come from the AISC Shapes Database v16.0.
W18x86 Dimensions
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Nominal weight | W | 86 lb/ft | 128 kg/m |
| Cross-sectional area | A | 25.3 in² | 16,300 mm² |
| Depth | d | 18.4 in | 467 mm |
| Flange width | bf | 11.1 in | 282 mm |
| Web thickness | tw | 0.48 in | 12.2 mm |
| Flange thickness | tf | 0.77 in | 19.6 mm |
| Distance to web toe of fillet (design) | kdes | 1.17 in | 29.7 mm |
| Distance to web toe of fillet (detailing) | kdet | 1.625 in | 41.3 mm |
| Web center line to flange toe of fillet | k1 | 1.0625 in | 27 mm |
| Distance between web toes of fillets | T | 15.125 in | 384 mm |
| Workable gage (inner holes) | WGi | 5.5 in | 140 mm |
W18x86 Section Properties
| Property | Symbol | Imperial | Metric |
|---|---|---|---|
| Moment of inertia, x-axis | Ix | 1,530 in⁴ | 637 ×10⁶ mm⁴ |
| Elastic section modulus, x-axis | Sx | 166 in³ | 2,720 ×10³ mm³ |
| Plastic section modulus, x-axis | Zx | 186 in³ | 3,050 ×10³ mm³ |
| Radius of gyration, x-axis | rx | 7.77 in | 197 mm |
| Moment of inertia, y-axis | Iy | 175 in⁴ | 72.8 ×10⁶ mm⁴ |
| Elastic section modulus, y-axis | Sy | 31.6 in³ | 518 ×10³ mm³ |
| Plastic section modulus, y-axis | Zy | 48.4 in³ | 793 ×10³ mm³ |
| Radius of gyration, y-axis | ry | 2.63 in | 66.8 mm |
| Torsional constant | J | 4.1 in⁴ | 1,710 ×10³ mm⁴ |
| Warping constant | Cw | 13,600 in⁶ | 3,650 ×10⁹ mm⁶ |
| Effective radius of gyration | rts | 3.05 in | 77.5 mm |
| Distance between flange centroids | ho | 17.6 in | 447 mm |
| Flange slenderness | bf/2tf | 7.2 | 7.2 |
| Web slenderness | h/tw | 33.4 | 33.4 |
W18x86 Weight Calculator
Enter a length to get the total weight of a W18x86 beam. A 20 ft length weighs 1,720 lb.
Uses the AISC nominal weight: 86 lb/ft (128 kg/m).
Beams Similar to W18x86
| Shape | Weight (lb/ft) | Depth (in) | Flange width (in) |
|---|---|---|---|
| W18x76 | 76 | 18.2 | 11 |
| W18x97 | 97 | 18.6 | 11.1 |
| W18x71 | 71 | 18.5 | 7.64 |
See every W18 size in the W18 beam sizes chart, or compare all shapes in the wide flange beam sizes chart. Working in millimetres? W18x86 is listed as W460x128 in the metric wide flange beam sizes chart.
W18x86 FAQ
What does W18x86 mean?
W means wide flange. The first number (18) is the nominal depth in inches, and the second number (86) is the weight in pounds per foot. The actual depth of W18x86 is 18.4 in. How to read steel beam sizes.
How much does a W18x86 beam weigh?
W18x86 weighs 86 lb per foot (128 kg per meter). A 20 ft beam weighs about 1,720 lb. Use the calculator above for any length.
What is the metric equivalent of W18x86?
The metric (SI) designation is W460x128: 467 mm deep with a 282 mm flange and 128 kg/m.
How far can a W18x86 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.