Round Bar Weight Calculator
Find round bar weight from diameter, length and material.
Results
Total weight
- Weight per unit length
- 0.61654 kg/m0.41429 lb/ft
- Weight per piece
- 0.61654 kg1.36 lb
- Cross-sectional area
- 78.54 mm²
- Volume per piece
- 7.85398E-5 m³
Presets are nominal densities. Alloy, dimensional tolerances and surface treatments affect actual mass. Holes and machined features are not included. Weight here means mass in kg or lb.
Formula · How it works
Formula
A = πD² / 4; V = A × L; m = V × ρ; mₜ = m × qCross-sectional area A = πD²/4. Volume per piece V = A × L. Weight per metre = A × ρ; mass per piece m = V × ρ; total mass = m × quantity. Dimensions are converted to m and density to kg/m³ before calculation.
Worked example
A 10 mm diameter carbon steel bar, 1 m long, has area 78.5398 mm² and volume 0.0000785398 m³. At a nominal density of 7,850 kg/m³, it weighs approximately 0.61654 kg per metre. Two 1 m pieces weigh 1.23308 kg.
How it works
The bar is modelled as a solid cylinder of uniform diameter and density. Weight per unit length is independent of piece length and quantity. Volume is shown for one piece; total weight includes the quantity.
Common questions
Can I use the density of a specific alloy?
Yes. Select custom density and enter the alloy density from the material specification in kg/m³ or lb/ft³. The same material presets are used by all four weight calculators.
How is weight per foot related to weight per metre?
One foot is 0.3048 m and one pound is 0.45359237 kg. Multiply kg/m by 0.3048 / 0.45359237 to obtain lb/ft. The calculator shows both equivalents.