W12X40 Dimensions & Weight

W12X40 is an AISC wide-flange (W) shape with an actual depth of 11.94 in and a 8.01 in wide flange, weighing 40 lb per foot — a common size for light floor framing, mezzanines, and residential beams.

W12X40 Dimensions

PropertyImperialMetric
Depth (d)11.94 in303.3 mm
Flange width (bf)8.01 in203.3 mm
Cross-section area (A)11.8 in²76.1 cm²
Weight40 lb/ft59.5 kg/m

What does W12X40 weigh and cost?

W12X40 weighs 40 lb per foot. At an example material price of $0.92/lb that is about $36.80 per foot. Set your quantity, length, and price to total your own run:

Total weight
800 lbs
Material cost
$736.00

Material only, example pricing. Actual steel pricing varies by region, grade, quantity, and market conditions — use your own supplier numbers for real bids.

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