W18x97 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W18x97 is an American wide-flange beam 18.6 inches (472.4 mm) deep with a 11.1 in (281.9 mm) flange, weighing 97 pounds per foot (144.4 kg/m) — that is what the "97" in the designation means. All values below are the standard AISC published section properties used in US structural design, with metric equivalents alongside.
Typical uses: floor and roof framing, columns, headers, and general steel construction. For a quick stiffness check, see the deflection example below or open the beam calculator with your own span and load.
Dimensions
| Depth d | 18.6 in (472.4 mm) |
| Flange width bf | 11.1 in (281.9 mm) |
| Web thickness tw | 0.535 in (13.6 mm) |
| Flange thickness tf | 0.87 in (22.1 mm) |
Weight & Cross-Section
| Weight per foot | 97 lb/ft (144.4 kg/m) |
| 20 ft bar | 1,940 lb |
| 40 ft bar | 3,880 lb |
| Area A | 28.5 in² (183.9 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 1,750 in⁴ (72,840 cm⁴) |
| Section modulus Sx | 188 in³ (3,081 cm³) |
| Radius of gyration rx | 7.82 in |
| Moment of inertia Iy | 201 in⁴ (8,366 cm⁴) |
| Section modulus Sy | 36.1 in³ (592 cm³) |
| Radius of gyration ry | 2.65 in |
Compared with the neighbouring sizes
| Shape | d × bf (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|---|---|---|---|---|---|
| W18x86 | 18.4 × 11.1 | 86 | 1,530 | 166 | −11 % | −13 % |
| W18x97 (this page) | 18.6 × 11.1 | 97 | 1,750 | 188 | — | — |
| W18x106 | 18.7 × 11.2 | 106 | 1,910 | 204 | +9 % | +9 % |
Deflection example
A simply supported W18x97 spanning 30 ft with a 10 kip point load at midspan deflects 0.19 in (E = 29,000 ksi, Ix = 1,750 in⁴). The L/360 serviceability limit for this span is 1 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W18x97 beam weigh?
W18x97 weighs 97 pounds per foot (144.4 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 1,940 lb and a 40 ft bar 3,880 lb.
What are the dimensions of a W18x97?
W18x97 is 18.6 in (472.4 mm) deep with a 11.1 in (281.9 mm) wide flange. The web is 0.54 in thick and the flanges are 0.87 in thick. Note the actual depth differs from the nominal W18 label — always design with the actual value.
What are the dimensions of a W18x97 in mm?
W18x97 is 472.4 mm deep with a 281.9 mm wide flange; the web is 13.6 mm and the flange 22.1 mm thick. In metric section properties: Ix = 72,840 cm⁴, Sx = 3,081 cm³.
How much does a W18x97 weigh in kg?
144.4 kg per meter. A 6 m bar weighs 866 kg and a 12 m bar 1,732 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W18x97?
About the strong axis, Ix = 1,750 in⁴ (72,840 cm⁴) with section modulus Sx = 188 in³. About the weak axis, Iy = 201 in⁴ and Sy = 36.1 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W18x97 or W18x106 — what does one size up change?
W18x106 is about 9% heavier (106 vs 97 lb/ft) but about 9% stiffer (Ix 1,910 vs 1,750 in⁴). Going one step up within the same depth group is usually the cheapest way to cut deflection.
Values are entered from the governing standard’s published tables and cross-checked programmatically against its mass and section formulas before publication. Spotted an error? Write to advertising@metalabout.net — verified corrections ship within days. About