Stainless Steel Weight Calculator
The grade list is stainless only: austenitic, ferritic, martensitic, duplex and super duplex, each at its own density. Choose the shape and the grade, enter the dimensions in millimetres or inches.
Sheet / plate
What this calculates
Every shape in the weight library — sheet and plate, round, square, flat and hex bar, pipe and tube, hollow section, equal angle — restricted to the stainless steel rows of the density table. The austenitic grades sit near 8000 kg/m³, ferritic and martensitic grades a little lower, so the grade choice moves the weight by a few percent.
The line under the grade names the density used — every stainless row is a named grade, so the figure is that grade's reference density, never a family guess. When the grade is still open, run the two candidates and carry both figures into the enquiry.
The weight is theoretical: nominal dimensions, no rolling tolerance. Stainless is normally sold on actual weight, so treat the figure as the sizing number and the quotation as the commercial one.
Show the formula and a worked example
The formula
- sheet / plate: W = L × W × t × ρ ÷ 10⁹
- round bar: W = π × (D ÷ 2)² × L × ρ ÷ 10⁹
- square bar: W = s² × L × ρ ÷ 10⁹
- flat bar: W = w × t × L × ρ ÷ 10⁹
- hex bar: W = (√3 ÷ 2) × AF² × L × ρ ÷ 10⁹
- pipe / tube: W = π ÷ 4 × (OD² − (OD − 2t)²) × L × ρ ÷ 10⁹
- RHS / SHS: W = (B × H − (B − 2t) × (H − 2t)) × L × ρ ÷ 10⁹
- equal angle: W = (2 × leg − t) × t × L × ρ ÷ 10⁹
Dimensions in millimetres, density ρ in kg/m³ — as the engine runs them.
Every shape reduces to cross-sectional area × length × density. Dimensions are in millimetres and density in kg/m³, so the product is divided by 10⁹ to land in kilograms; the per-metre readout is the same calculation run at a one-metre length.
The hollow shapes subtract the bore from the outer section. The hollow-section and angle areas ignore corner radii; the mill's section table gives the catalogue weight for a standard size.
Worked example
| Shape | Flat bar |
|---|---|
| Width | 50 mm |
| Thickness | 10 mm |
| Length | 6000 mm |
| Material grade | 304 |
| Density | 8,000 kg/m³ · grade density |
| Theoretical weight | 24 kg |
| Per metre | 4 kg/m |
Computed by the calculation engine from these inputs at render time, rounded only for display.
Frequently asked
- 01Is 316 heavier than 304?
- Marginally. The density table carries both at 8000 kg/m³ as reference values, so on this page they weigh the same; real heats differ by well under a percent. Choose the grade that the specification asks for, not the lighter one.
- 02Which stainless grades are in the list?
- The stainless rows of the density table: the 200- and 300-series austenitics including 304, 304L, 316, 316L, 321 and 310S, the ferritic and martensitic 400-series, and the duplex and super duplex grades. Missing one? Run the nearest grade and name the actual one in the enquiry; the density difference within a series is under a percent.
- 03Does the finish change the weight?
- Not measurably. A polished, brushed or PVD-coated surface removes or adds a few microns; the calculation ignores it and so does the mill certificate.
- 04What is a theoretical weight?
- The weight of the nominal geometry at the reference density. Actual pieces are rolled or drawn to a tolerance, so the certificate weight differs slightly. The quotation states the basis it is priced on.