Steel tubular sizes and weights.
Square and rectangular hollow sections in mild steel (A500 / SS400), black or galvanized, sold by outside dimensions in inches and wall thickness, standard 6.0m lengths. Weight formula: kg/m = [2t(a + b) − 4t²] × 0.00785.
Sizes and weights
A500 / JIS SS400 · theoretical weights (sharp-corner formula)
| Size (in) | Dims (mm) | Wall (mm) | kg/m | kg per 6.0 m |
|---|---|---|---|---|
| 1 × 1 | 25 × 25 | 1 | 0.75 | 4.52 |
| 1 × 1 | 25 × 25 | 1.2 | 0.9 | 5.38 |
| 1 × 1 | 25 × 25 | 1.5 | 1.11 | 6.64 |
| 1 × 1 | 25 × 25 | 2 | 1.44 | 8.67 |
| 1-1/2 × 1-1/2 | 38 × 38 | 1.2 | 1.39 | 8.33 |
| 1-1/2 × 1-1/2 | 38 × 38 | 1.5 | 1.72 | 10.31 |
| 1-1/2 × 1-1/2 | 38 × 38 | 2 | 2.26 | 13.57 |
| 2 × 2 | 50 × 50 | 1.2 | 1.84 | 11.04 |
| 2 × 2 | 50 × 50 | 1.5 | 2.28 | 13.7 |
| 2 × 2 | 50 × 50 | 2 | 3.01 | 18.08 |
| 1 × 2 | 25 × 50 | 1.2 | 1.37 | 8.22 |
| 1 × 2 | 25 × 50 | 1.5 | 1.7 | 10.18 |
| 1 × 2 | 25 × 50 | 2 | 2.23 | 13.37 |
| 1 × 3 | 25 × 75 | 1.5 | 2.28 | 13.7 |
| 1 × 3 | 25 × 75 | 2 | 3.01 | 18.08 |
| 2 × 3 | 50 × 75 | 1.5 | 2.87 | 17.24 |
| 2 × 3 | 50 × 75 | 2 | 3.8 | 22.79 |
| 2 × 4 | 50 × 100 | 1.5 | 3.46 | 20.77 |
| 2 × 4 | 50 × 100 | 2 | 4.58 | 27.5 |
Weights are theoretical (sharp-corner formula at 7.85 g/cm³). Real tube has rounded corners and gauge tolerance, so actual weight runs a few percent off — more at thicker walls. Exact weight is confirmed on your quote.
Grades
- A500 / JIS SS400 mild steel, black or galvanized; walls 0.8–2.0mm common, up to ~4.0mm by order.
How it's sold
Sold per 6.0m length by size, wall and finish (black or GI). Send your tube list and we quote it the same day. Send your list — spec sheet, drawing or BOQ — and we quote it back the same day.
Common questions
Square vs rectangular tube?
Both are hollow sections sold by outside dimensions and wall. Used for frames, railings, gates, trusses, furniture and canopies.
Are these weights exact?
They are theoretical. Supplier tables differ a few percent because of rounded corners and coil gauge tolerance; we confirm actual weight per brand on the quote.
What is the tube weight formula?
kg/m = [2 × t × (a + b) − 4 × t²] × 0.00785, with outside dims a, b and wall t in mm.
Related steel
Specs reviewed July 2026 · Southend Construction & Industrial Supplies, Dasmariñas, Cavite