Steel Beam Weight Calculator Formula

Understand the math behind the steel beam weight calculator. Each variable explained with a worked example.

Formulas Used

Weight per Beam

single_weight = weight_per_foot * beam_length

Total Weight

total_weight = weight_per_foot * beam_length * quantity

Total Weight

total_tons = weight_per_foot * beam_length * quantity / 2000

Variables

VariableDescriptionDefault
weight_per_footBeam Weight(lb/ft)31
beam_lengthBeam Length(ft)20
quantityNumber of Beams1

How It Works

Steel Beam Weight

Weight = Weight per Foot x Length

Steel beams are designated by their weight per linear foot (e.g., W8x31 weighs 31 lbs/ft). Multiply by the cut length to get the total weight for ordering, shipping, and crane planning.

Worked Example

One W8x31 beam, 20 feet long.

weight_per_foot = 31beam_length = 20quantity = 1
  1. 01Weight = 31 x 20 = 620 lbs
  2. 02Total = 620 lbs = 0.31 tons

Ready to run the numbers?

Open Steel Beam Weight Calculator