Metal Weight Per Foot Calculator

Bar Stock Weight Starts With Cross-Section, Not Length

A linear foot of steel bar can weigh anywhere from under a pound to several pounds depending entirely on its cross-sectional shape and material — a round bar, a square bar, and a tube of the same nominal size all carry different amounts of metal per foot. Getting weight-per-foot right is what turns a bar length into a number a scale or a freight quote can use.

The Formula

Weight per Foot = Cross-Sectional Area × 12 in × Density

Cross-sectional area depends on the shape selected — a circle for round bar, a square for square bar, a rectangle for rectangular bar, or an annulus (outer circle minus inner circle) for round tube.

Worked Examples

Weight per foot by shape and material
ShapeDimensionsMaterialCross-Section AreaWeight per Foot
Round bar1 in diameterMild Steel0.7854 in²2.673 lb/ft (3.978 kg/m)
Round bar0.5 in diameterAluminum0.1963 in²0.230 lb/ft (0.342 kg/m)
Round tube1 in OD, 0.065 in wallMild Steel0.1909 in²0.650 lb/ft (0.967 kg/m)

A 1-inch OD tube with a 0.065-inch wall weighs less than a quarter of what a solid 1-inch round bar of the same material weighs — the hollow center removes most of the cross-sectional area, which is exactly why tube is chosen when strength-to-weight matters more than raw strength.

Where This Calculation Matters

  • Material ordering — converting a required bar length into a weight for pricing, since bar stock is frequently sold by weight.
  • Shipping weight estimation — calculating total shipment weight from a bill of materials listing bar lengths and sizes.
  • Weight-critical design — comparing solid versus tubular stock of equivalent size to see the weight savings a hollow section offers.

How to Use This Calculator

  1. Choose the shape: Round Bar, Square Bar, Rectangular Bar, or Round Tube.
  2. Enter the relevant dimensions — Diameter (in) for round, Side Length (in) for square, Width (in) and Height (in) for rectangular, or Outer Diameter (in) and Wall Thickness (in) for tube.
  3. Select the material from the list.
  4. Select Calculate to get weight per foot in both pounds and kilograms per meter.

Related Calculations

For flat sheet stock rather than bar or tube, use the Sheet Metal Weight Calculator.