Section Steel Weight Calculator
Pick a section type, enter height, flange width and thickness to get weight per metre, per piece and total tonnage.
Quick answer
With the default inputs: Section type H-beam · Section height h 200 · Flange width b 200 etc.Theoretical weight per metre 48.73 kg/m
Edit the inputs below to recalculate.Inputs
Result
Theoretical weight per metre
48.73kg/m
| Section area | 6208mm² |
| Weight per piece | 584.79kg |
| Total weight | 5847.9kg |
| Total tonnage | 5.848t |
| Density used | 7850kg/m³ |
Rectangular approximation without root radii, typically 1-3% lighter than the GB/T 706 section tables. Use official mill tables for ordering and settlement.
Reverse: known result, work out one input
Enter a target result; the other inputs stay fixed and this one is worked out.
Formula
| H / I beam area | A = 2 × b × tf + (h − 2tf) × tw |
| Channel area | A = h × tw + 2 × b × tf |
| Weight per metre | g = A(mm²) × 7.85 ÷ 1000 (kg/m) |
| Total weight | W = g × length × quantity |
HW200×200×8×12, 12 m long, 10 pieces: A = 6208 mm², 48.73 kg/m, 584.8 kg each, 5.85 t total (the GB table gives 49.9 kg/m; the gap is the root radius).
How to work it out
- Expand the section area by type: H-section A = 2b·tf + (h − 2tf)·tw; rectangular hollow A = 2(h + b − 2t)t; circular hollow A = π(D − t)t.
- Unit weight = area (mm²) × 0.00785 ÷ 1000, or simply read the section table, which is both quicker and more accurate.
- Multiply by length and count for the total tonnage.
- H-sections come as HW (wide flange), HM (medium) and HN (narrow); the same depth in different series differs enormously in weight, so depth alone tells you nothing.
- Welded H-sections use the same formula, but add 1-3% for weld metal and allow for plus tolerance on flange width.
Where it goes wrong
- Selecting on depth only — HN400×200 is 66 kg/m and HW400×400 is 172 kg/m, 2.6 times heavier at the same 400 depth.
- Using h instead of (h − 2tf) for the web — the web runs between the flanges, and the error is exactly the two flange thicknesses.
- Applying the formula to hot-rolled sections — rolled sections have root radii, so the formula understates area by 1-3%; use tables for bulk work.
- Ignoring minus tolerance — flange and web thickness both run under, so theoretical weight often exceeds the delivery by 2-5%.
Material and cost
Q235 H-section 4200-5000 CNY/t, Q355 4600-5600, welded H-section 4500-5500 including fabrication, hot-dip galvanising adds 800-1200.
On site
- The strong axis is x (about the web) and the weak axis y (about the flanges); columns must be oriented for the strong axis, not rotated 90° for convenience.
- HN suits beams and HW suits columns — check the intended use before selecting.
- The flange-to-web fillet weld in a welded H-section is designed, not just run; flanges over 16 mm need a bevel preparation.
Basis
- GB/T 11263-2017 Hot-rolled H-beams and split T-sections
- GB/T 706-2016 Hot-rolled section steel
- GB 50017-2017 Standard for design of steel structures
- GB 50205-2020 Code for acceptance of steel structure construction
FAQ
Why is the result slightly lighter than the mill table?
The section is treated as joined rectangles, ignoring root radii at the flange-web junction, which add real material (about 2% for HW200×200). A 1-3% gap is normal; a 10% gap means a wrong input, typically using a channel's overall width instead of one flange.
What actually differs between H-beams, I-beams and channels?
I-beams have tapered inner flange faces and poor lateral resistance at greater depths. H-beams have parallel, equal-thickness flanges and a wide flange, giving good bending and torsional behaviour (HW wide, HM medium, HN narrow). Channels are open C sections used for purlins and bracing; they are singly symmetric and buckle laterally under compression.
Why 7850 kg/m³ for steel?
7850 kg/m³ (7.85 g/cm³) is the conventional density for carbon structural steel used by GB/T 709 and the section tables. Stainless is about 7930, aluminium 2700, cast iron 7200. Mixing densities between parties creates a few per mille of drift, so agree on one.
Cite this page
Use this format in reports, method statements or coursework. The link is permanent.
Building Calculator. Section Steel Weight Calculator. 2026-10-25. https://jianzhujisuan.com/en/section-steel-weight
Results are estimating aids only and are not a design basis. Construction and final accounts must follow the drawings, the applicable standards and an approved method statement. Anything affecting structural safety, shoring or falsework must be checked by a suitably qualified engineer.