Metal Weight Calculator

Estimate the weight of a metal part or stock cut in seconds. Pick a shape and alloy, enter the dimensions in inches or millimeters, and get the theoretical weight per piece and for the full quantity — in both pounds and kilograms. Handy for quoting freight, estimating material cost, and sizing up a cut before you call around for stock.

Calculate weight

Enter the dimensions above to estimate weight. Theoretical weight uses nominal density and does not account for tolerances, mill variation, or coatings.

How metal weight is calculated

Weight = volume × density. For a length of bar or tube, the volume is the cross-sectional area times the length; for plate and sheet it is length × width × thickness. The cross-section depends on the shape:

  • Round bar: π/4 × diameter²
  • Square bar: side²
  • Rectangular bar: width × height
  • Hex bar: (√3 / 2) × across-flats²
  • Round tube: π/4 × (OD² − ID²)

Multiply the volume by the alloy density to get mass. This is theoretical weight; real stock varies with tolerances, finish, and coatings.

Metal density reference

Materialg/cm³lb/in³
Carbon steel (A36 / 1018)7.850.284
Stainless steel 304 / 3168.000.289
Aluminum 60612.700.098
Aluminum 70752.810.102
Brass (C360)8.500.307
Copper (C110)8.960.324
Titanium (Grade 5)4.430.160

Need the metal itself? Browse U.S. metal suppliers by material, shape, and location.

Frequently asked questions

How do you calculate the weight of a metal part?
Weight equals volume times density. Find the volume from the part geometry (for a bar, the cross-sectional area times length; for a plate, length times width times thickness), then multiply by the alloy density. This calculator does that for common bar, plate, sheet, tube, and pipe shapes.
Is this theoretical or actual weight?
It is theoretical weight based on nominal density. Real stock varies with mill tolerances, surface finish, and coatings, so actual weight can differ by a few percent. Use it for estimating freight, material cost, and handling — not as a certified figure.
What density does it use for steel and aluminum?
Carbon steel uses 7.85 g/cm³ (0.284 lb/in³) and aluminum 6061 uses 2.70 g/cm³ (0.098 lb/in³). See the density table on this page for the full list.

Need it made?

Upload a drawing or STEP file and get quotes from verified U.S. suppliers — cutting, machining, fabrication, and finishing.

Get quotes from U.S. suppliers