Match the actual shape
Choose solid rectangle, solid round bar, round tube or rectangular hollow section. Only dimensions relevant to that shape are required.
LIFTING & RIGGING / TOOL 06
Steel and Material Weight Calculator
Use this to estimate the mass of a uniform plate, round bar, tube or rectangular hollow section when dimensions are available but a weighing record is not.
Before you start: required inputs
- Identify the material and obtain its density from the material specification; the example uses 7,850 kg/m³ for steel.
- Measure one piece in millimetres. For a hollow section, use outside dimensions and wall thickness rather than internal dimensions.
Calculation diagram
A PRACTICAL WALKTHROUGH
How to use this calculator
Set density and dimensions
Enter the piece length and section dimensions in millimetres, then the number of identical pieces.
Separate piece mass from batch mass
Use mass per piece for a single item and total mass for the entire entered quantity. Add contents and lifting accessories elsewhere.
One steel plate, 1,000 × 100 × 5 mm
THE INPUTS
Shape solid rectangular plate; density 7,850 kg/m³; length 1,000 mm; width 100 mm; thickness 5 mm; quantity 1.
THE RESULT
Material volume is 0.0005 m³ and mass is 3.925 kg. The mass per metre is also 3.925 kg/m because the example piece is 1 m long.
What does the result mean?
01
Total material mass multiplies the mass per piece by the entered quantity.
02
Mass per metre lets you compare lengths of the same section without changing the section dimensions.
03
The model uses nominal geometry. Corner radii, coatings, welds, tolerances and any material inside a tube are excluded.
Watch for this
Entering metres into millimetre fields, or choosing a solid bar for a hollow tube. Either mistake can produce a large mass error.
Formula & model conditions +
Mass = cross-sectional area × length × density × quantity (use m², m and kg/m³)
Solid rectangular area = B × H; solid round area = πD² / 4
Round tube area = π × [D² − (D − 2t)²] / 4
Box area = B × H − (B − 2t) × (H − 2t)
- Constant section, uniform density and identical pieces are assumed.
- Tube and hollow-section walls have constant thickness; corner radii, welds, coatings and manufacturing tolerances are excluded.
- Calculated material mass excludes lifting accessories and contents.
Common questions
Can I calculate a filled tube or concrete-filled box?
Calculate the metal and its contents separately with their own densities and dimensions, then add their masses.
Will the result match a supplier’s exact section mass?
Not necessarily. Supplier tables may include actual corner geometry and manufacturing conventions that this sharp-corner model excludes.