W12x170 — Dimensions, Weight & Section Properties
American wide-flange (W) beam per ASTM A6 / AISC Steel Construction Manual
W12x170 is an American wide-flange beam 14 inches (355.6 mm) deep with a 12.6 in (320 mm) flange, weighing 170 pounds per foot (253 kg/m) — that is what the "170" 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 | 14 in (355.6 mm) |
| Flange width bf | 12.6 in (320 mm) |
| Web thickness tw | 0.96 in (24.4 mm) |
| Flange thickness tf | 1.56 in (39.6 mm) |
Weight & Cross-Section
| Weight per foot | 170 lb/ft (253 kg/m) |
| 20 ft bar | 3,400 lb |
| 40 ft bar | 6,800 lb |
| Area A | 50 in² (322.6 cm²) |
Section Properties (strong / weak axis)
| Moment of inertia Ix | 1,650 in⁴ (68,678 cm⁴) |
| Section modulus Sx | 235 in³ (3,851 cm³) |
| Radius of gyration rx | 5.74 in |
| Moment of inertia Iy | 517 in⁴ (21,519 cm⁴) |
| Section modulus Sy | 82.3 in³ (1,349 cm³) |
| Radius of gyration ry | 3.22 in |
Compared with the neighbouring sizes
| Shape | d × bf (in) | lb/ft | Ix (in⁴) | Sx (in³) | Δ weight | Δ Ix |
|---|---|---|---|---|---|---|
| W12x152 | 13.7 × 12.5 | 152 | 1,430 | 209 | −11 % | −13 % |
| W12x170 (this page) | 14 × 12.6 | 170 | 1,650 | 235 | — | — |
| W12x190 | 14.4 × 12.7 | 190 | 1,890 | 263 | +12 % | +15 % |
Deflection example
A simply supported W12x170 spanning 22 ft with a 10 kip point load at midspan deflects 0.08 in (E = 29,000 ksi, Ix = 1,650 in⁴). The L/360 serviceability limit for this span is 0.73 in — the shape passes this quick check.
Calculate with your own span and load →
Frequently asked questions
How much does a W12x170 beam weigh?
W12x170 weighs 170 pounds per foot (253 kg/m). The number after the "x" in the designation is always the weight in lb/ft. A 20 ft bar weighs 3,400 lb and a 40 ft bar 6,800 lb.
What are the dimensions of a W12x170?
W12x170 is 14 in (355.6 mm) deep with a 12.6 in (320 mm) wide flange. The web is 0.96 in thick and the flanges are 1.56 in thick. Note the actual depth differs from the nominal W12 label — always design with the actual value.
What are the dimensions of a W12x170 in mm?
W12x170 is 355.6 mm deep with a 320 mm wide flange; the web is 24.4 mm and the flange 39.6 mm thick. In metric section properties: Ix = 68,678 cm⁴, Sx = 3,851 cm³.
How much does a W12x170 weigh in kg?
253 kg per meter. A 6 m bar weighs 1,518 kg and a 12 m bar 3,036 kg — handy when ordering US shapes from metric suppliers.
What is the moment of inertia of a W12x170?
About the strong axis, Ix = 1,650 in⁴ (68,678 cm⁴) with section modulus Sx = 235 in³. About the weak axis, Iy = 517 in⁴ and Sy = 82.3 in³. Use the beam deflection calculator to turn these into deflection and stress for your span and load.
W12x170 or W12x190 — what does one size up change?
W12x190 is about 12% heavier (190 vs 170 lb/ft) but about 15% stiffer (Ix 1,890 vs 1,650 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