Tube Weight Calculator
Pick round, square or rectangular tube, enter its size, wall and length, and get the weight of each piece and per metre or foot.
At a glance
Tube Weight Calculator is a free browser tool that takes the outside size, wall thickness and length of round, square or rectangular tube in any listed metal and returns the weight of each piece and the weight per metre or foot.
- Round tube area is π × wall × (OD − wall), and weight is that area × length × density.
- A 50 mm OD, 3 mm wall steel tube weighs 3.477 kg/m, so a 6 m piece weighs 20.86 kg.
- A 2 × 2 in square steel tube with a 1/8 in wall weighs 3.190 lb per foot, so a 20 ft length weighs 63.81 lb.
- A 40 × 40 × 3 mm square steel tube weighs 3.485 kg/m, calculated with sharp corners, so rounded real-world corners can differ slightly from catalogue weights.
- Wall thickness must be less than half the smallest outside dimension, and the tool shows an error if it is not.
Sources: Tube (fluid conveyance) (Wikipedia) (checked 2026-10-15)
How to use the tube weight calculator
- Set the units with the Metric (mm) / Imperial (in) switch at the top of the tool.
- In Shape, choose Round tube (own OD and wall), Square tube or Rectangular tube. For standard pipe sizes, use the pipe weight calculator instead.
- In Material, pick mild steel, stainless steel 304 or 316, aluminum, copper or another option. For anything not listed, choose Custom density and type in its density.
- Enter the size controls for your shape:
- Round tube: Outside diameter (OD) and Wall thickness.
- Square tube: Side (outside) and Wall thickness.
- Rectangular tube: Width (outside), Height (outside) and Wall thickness.
- Enter the Length of one piece.
- Enter the Number of pieces. If it is more than 1, the tool also shows Total weight.
- (Optional) Open More options and enter a Price per kg (metric) or per lb (imperial) to add a material cost.
- Read the results: Weight of one piece, Weight per length, Cross-section area, Volume of one piece and Density used. Check the cross-section sketch and the calculation steps, and read any warning under the result.
Enter the outside size of the tube, not its inside diameter, which is a common mistake. Under the result, Print / save result prints the inputs, results, calculation steps and date. Choose Save as PDF in the browser’s print dialog to keep a PDF. Copy link reopens the page with the same inputs, and Reset starts over.
How to calculate steel tube weight
Multiply the metal area of the tube’s cross-section by its length and by the material’s density. For mild steel the density is 7.85 g/cm³, which equals 7,850 kg/m³ or 0.2836 lb/in³.
The formula is: weight = area × length × density. The area depends on the shape, where wall is the wall thickness:
- Round tube: area = π × wall × (OD − wall)
- Square tube: area = 4 × wall × (side − wall)
- Rectangular tube: area = W × H − (W − 2 × wall) × (H − 2 × wall)
As a check, a round steel tube of 50 mm OD and 3 mm wall weighs 3.477 kg/m, so a 6 m piece weighs 20.86 kg.
Steel tube weight per foot
Steel tube weight per foot is the weight of one foot of tube, the imperial version of weight per length. The tool shows it in lb/ft when Imperial (in) is selected. For example, a 2 × 2 in square steel tube with a 1/8 in wall weighs 3.190 lb per foot, so a 20 ft length weighs 63.81 lb. To work it out yourself, multiply the weight per foot by the length in feet.
Why do square and rectangular tube weights differ from catalogue values?
The tool calculates square and rectangular tube with sharp outer and inner corners. Real tube has rounded corners, so catalogue weights differ slightly, especially for thick walls. The tool shows this as a warning under the result. For exact values, use the mill table from your supplier.
Examples from the tool: a 40 × 40 × 3 mm square steel tube weighs 3.485 kg/m (20.91 kg for 6 m), and a 60 × 40 × 3 mm rectangular steel tube weighs 4.427 kg/m (26.56 kg for 6 m).
Tube weight chart
Weight per metre from the tool for round tube (steel 7.85, aluminum 6061 2.70, stainless 304 8.00 g/cm³):
| Round tube OD × wall | Steel kg/m | Aluminum 6061 kg/m | Stainless 304 kg/m |
|---|---|---|---|
| 20 × 2 mm | 0.888 | 0.305 | 0.905 |
| 25 × 2 mm | 1.134 | 0.390 | 1.156 |
| 32 × 2.5 mm | 1.819 | 0.626 | 1.854 |
| 40 × 3 mm | 2.737 | 0.942 | 2.790 |
| 50 × 3 mm | 3.477 | 1.196 | 3.544 |
| 60 × 3 mm | 4.217 | 1.450 | 4.298 |
| 76 × 4 mm | 7.103 | 2.443 | 7.238 |
And for square tube, calculated with sharp corners (see the note above about catalogue values):
| Square tube side × wall | Steel kg/m | Aluminum 6061 kg/m |
|---|---|---|
| 20 × 20 × 2 mm | 1.130 | 0.389 |
| 25 × 25 × 2 mm | 1.444 | 0.497 |
| 30 × 30 × 2 mm | 1.758 | 0.605 |
| 40 × 40 × 3 mm | 3.485 | 1.199 |
| 50 × 50 × 3 mm | 4.427 | 1.523 |
| 60 × 60 × 4 mm | 7.034 | 2.419 |
| 80 × 80 × 4 mm | 9.546 | 3.283 |
Sources
Data and rules used by this tool (checked October 2026):
Frequently asked questions
Can I use this as a stainless steel tube weight calculator?
Yes. Choose Stainless steel 304 or 316 from the material list. Its density is 8.00 g/cm³, slightly higher than mild steel’s 7.85 g/cm³, so the same tube weighs a little more.
How do I enter a tube that is sold by gauge?
Look up the wall thickness on the sheet metal gauge chart and type it into Wall thickness. Keep the outside dimension as your size.
Why does the tool show an error?
Wall thickness must be less than half the smallest outside dimension. Check that you entered the outside size, not the inside diameter.
Is this the same as the pipe weight calculator?
Not quite. The pipe calculator picks a standard NPS size and schedule. This page takes the outside size and wall you type, so it fits tube sold by its own dimensions.
Can I use the results in a quote or a product I sell?
Yes. Results may be used in commercial work, royalty-free, with no attribution required. The only limit is copying the site itself as a competing service. Results are for estimation, so verify critical designs against the applicable standard.
Does it work for aluminum tube?
Yes. Choose Aluminum 6061 (2.70 g/cm³), 5052 (2.68) or 7075 (2.81). The same 60 × 40 × 3 mm rectangular tube weighs 1.523 kg/m in aluminum 6061, compared with 4.427 kg/m in steel.
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