W10x45 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W10x45 is an American wide-flange beam 10.1 inches (256.5 mm) deep with a 8.02 in (203.7 mm) flange, weighing 45 pounds per foot (67 kg/m) — that is what the "45" 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 | 10.1 in (256.5 mm) |
| Flange width bf | 8.02 in (203.7 mm) |
| Web thickness tw | 0.35 in (8.9 mm) |
| Flange thickness tf | 0.62 in (15.7 mm) |
Weight & Cross-Section
| Weight per foot | 45 lb/ft (67 kg/m) |
| 20 ft bar | 900 lb |
| 40 ft bar | 1,800 lb |
| Area A | 13.3 in² (85.8 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 248 in⁴ (10,323 cm⁴) |
| Section modulus Sx | 49.1 in³ (805 cm³) |
| Radius of gyration rx | 4.32 in |
| Moment of inertia Iy | 53.4 in⁴ (2,223 cm⁴) |
| Section modulus Sy | 13.3 in³ (218 cm³) |
| Radius of gyration ry | 2.01 in |
Compared with the neighbouring sizes
| Shape | d × bf (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|---|---|---|---|---|---|
| W10x39 | 9.92 × 7.99 | 39 | 209 | 42.1 | −13 % | −16 % |
| W10x45 (this page) | 10.1 × 8.02 | 45 | 248 | 49.1 | — | — |
| W10x49 | 9.98 × 10 | 49 | 272 | 54.6 | +9 % | +10 % |
Deflection example
A simply supported W10x45 spanning 16 ft with a 10 kip point load at midspan deflects 0.21 in (E = 29,000 ksi, Ix = 248 in⁴). The L/360 serviceability limit for this span is 0.53 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W10x45 beam weigh?
W10x45 weighs 45 pounds per foot (67 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 900 lb and a 40 ft bar 1,800 lb.
What are the dimensions of a W10x45?
W10x45 is 10.1 in (256.5 mm) deep with a 8.02 in (203.7 mm) wide flange. The web is 0.35 in thick and the flanges are 0.62 in thick. Note the actual depth differs from the nominal W10 label — always design with the actual value.
What are the dimensions of a W10x45 in mm?
W10x45 is 256.5 mm deep with a 203.7 mm wide flange; the web is 8.9 mm and the flange 15.7 mm thick. In metric section properties: Ix = 10,323 cm⁴, Sx = 805 cm³.
How much does a W10x45 weigh in kg?
67 kg per meter. A 6 m bar weighs 402 kg and a 12 m bar 804 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W10x45?
About the strong axis, Ix = 248 in⁴ (10,323 cm⁴) with section modulus Sx = 49.1 in³. About the weak axis, Iy = 53.4 in⁴ and Sy = 13.3 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W10x45 or W10x49 — what does one size up change?
W10x49 is about 9% heavier (49 vs 45 lb/ft) but about 10% stiffer (Ix 272 vs 248 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