W10x100 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W10x100 is an American wide-flange beam 11.1 inches (281.9 mm) deep with a 10.3 in (261.6 mm) flange, weighing 100 pounds per foot (148.8 kg/m) — that is what the "100" 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 | 11.1 in (281.9 mm) |
| Flange width bf | 10.3 in (261.6 mm) |
| Web thickness tw | 0.68 in (17.3 mm) |
| Flange thickness tf | 1.12 in (28.4 mm) |
Weight & Cross-Section
| Weight per foot | 100 lb/ft (148.8 kg/m) |
| 20 ft bar | 2,000 lb |
| 40 ft bar | 4,000 lb |
| Area A | 29.4 in² (189.7 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 623 in⁴ (25,931 cm⁴) |
| Section modulus Sx | 112 in³ (1,835 cm³) |
| Radius of gyration rx | 4.6 in |
| Moment of inertia Iy | 207 in⁴ (8,616 cm⁴) |
| Section modulus Sy | 40 in³ (655 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 |
|---|---|---|---|---|---|---|
| W10x88 | 10.8 × 10.3 | 88 | 534 | 98.5 | −12 % | −14 % |
| W10x100 (this page) | 11.1 × 10.3 | 100 | 623 | 112 | — | — |
| W10x112 | 11.4 × 10.4 | 112 | 716 | 126 | +12 % | +15 % |
Deflection example
A simply supported W10x100 spanning 18 ft with a 10 kip point load at midspan deflects 0.12 in (E = 29,000 ksi, Ix = 623 in⁴). The L/360 serviceability limit for this span is 0.6 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W10x100 beam weigh?
W10x100 weighs 100 pounds per foot (148.8 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 2,000 lb and a 40 ft bar 4,000 lb.
What are the dimensions of a W10x100?
W10x100 is 11.1 in (281.9 mm) deep with a 10.3 in (261.6 mm) wide flange. The web is 0.68 in thick and the flanges are 1.12 in thick. Note the actual depth differs from the nominal W10 label — always design with the actual value.
What are the dimensions of a W10x100 in mm?
W10x100 is 281.9 mm deep with a 261.6 mm wide flange; the web is 17.3 mm and the flange 28.4 mm thick. In metric section properties: Ix = 25,931 cm⁴, Sx = 1,835 cm³.
How much does a W10x100 weigh in kg?
148.8 kg per meter. A 6 m bar weighs 893 kg and a 12 m bar 1,786 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W10x100?
About the strong axis, Ix = 623 in⁴ (25,931 cm⁴) with section modulus Sx = 112 in³. About the weak axis, Iy = 207 in⁴ and Sy = 40 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W10x100 or W10x112 — what does one size up change?
W10x112 is about 12% heavier (112 vs 100 lb/ft) but about 15% stiffer (Ix 716 vs 623 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