Steel and metal weight calculator.
Calculate the weight of steel or metal sections for ordering and costing. Pick a profile — round bar, round pipe/tube, square bar or flat plate — enter its dimensions and length, and this calculator finds the weight from a standard cross-sectional-area formula, not a lookup table, so it holds for any size. Choose the material (mild/carbon steel, stainless, aluminium or cast iron) to use the right density, and add an offcut/waste allowance for ordering. This is for ordering and costing steel, not a substitute for a fabrication drawing or mill certificate. Use our Rebar Weight Calculator for reinforcement bar specifically.
Drop an Excel or CSV file or to replace the table below.
Column A: item/mark name. Column B: length. Columns C-E (optional): profile, diameter/width and wall/plate thickness — rows without a recognised profile default to round bar.
Parsed entirely in your browser — your file is never uploaded to our servers.
| Item / mark | Length (m) | Profile | Diameter / width (mm) | Wall / plate thickness (mm) | Quantity | Weight (kg) | Row actions |
|---|---|---|---|---|---|---|---|
| — | |||||||
| — | |||||||
| — |
How we calculate this.
Calculate the weight of steel or metal sections for ordering and costing. Pick a profile — round bar, round pipe/tube, square bar or flat plate — enter its dimensions and length, and this calculator finds the weight from a standard cross-sectional-area formula, not a lookup table, so it holds for any size. Choose the material (mild/carbon steel, stainless, aluminium or cast iron) to use the right density, and add an offcut/waste allowance for ordering. This is for ordering and costing steel, not a substitute for a fabrication drawing or mill certificate. Use our Rebar Weight Calculator for reinforcement bar specifically.
For each item (row), a cross-sectional area is found from the selected profile: π/4 × diameter² for a round bar, π/4 × (outer² − inner²) for a pipe/tube (inner = outer − 2 × wall thickness), side² for a square bar, or width × thickness for a flat plate. weight = area × length × density, using the selected material's density. The total across every row is summed, then a shared offcut/waste allowance is added on top for the ordering total.
| Assumption | Value | Source |
|---|---|---|
| Cross-sectional area | π/4 × d² (round), π/4 × (D² − d²) (pipe), s² (square), w × t (plate) | Standard geometric cross-sectional-area formulas for solid round, hollow round (tube/pipe), solid square and flat rectangular sections — universal, not material- or standard-specific. |
| Mild / carbon steel density | 7,850 kg/m³ | Standard published steel density, the same value already used by the Rebar Weight Calculator on this site — consistent with BS 4449 / ASTM A615 nominal mass conventions. |
| Stainless steel density | 8,000 kg/m³ | Standard published density for austenitic stainless steel grades (e.g. 304/316) — widely cited across steel-supplier reference tables. |
| Aluminium density | 2,700 kg/m³ | Standard published density for 6061-series aluminium alloy, the common structural/fabrication grade. |
| Cast iron density | 7,200 kg/m³ | Standard published density for grey cast iron — widely cited reference value. |
| Offcut / waste allowance | 0–20%, default 5% | Typical allowance for cutting waste and offcuts on a steel/metal takeoff — general estimating practice, confirm against your own fabrication schedule. |
This is an early-appraisal planning estimate, not a quotation or a substitute for a surveyed takeoff. Last reviewed 30 Aug 2026.
Pick the material from the dropdown — mild/carbon steel (7,850 kg/m³), stainless steel (8,000 kg/m³), aluminium (2,700 kg/m³) or cast iron (7,200 kg/m³). All four are standard published values.
Yes — select the material for each takeoff from the Material dropdown above the table; every row in that takeoff uses the selected material's density.
Choose the profile per row: for a flat plate, enter its width as the diameter/width field and its thickness as the wall/plate-thickness field. For a round or square bar, only the diameter/width field is used.
No. This estimates total weight for ordering and costing — the actual fabrication drawing, with connection details and exact cut lengths, still needs a qualified engineer or detailer.
Yes — click or drop an Excel (.xlsx/.xls) or CSV file onto the upload area. The first column should be an item name and the second the measurement for that row; extra columns this calculator uses are read too if present. The file is parsed entirely in your browser — it's never uploaded to our servers. Download the blank template first if you're not sure of the layout.
Yes — use the metric/imperial switch above the calculator. Values you've already entered convert automatically; nothing is lost switching back and forth.
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