Tube Weight Calculator
Choose round, square, and rectangular tube from the shape list, then enter actual outside dimensions, wall thickness, length, quantity, and material. Use the theoretical weight for takeoffs and compare structural sections with the applicable product table.
Planning a purchase? See what to include in your enquiry
Use this checklist when asking a supplier for a quote. Mark anything you are unsure about for confirmation.
- Material
- Grade and any specified material standard.
- Dimensions
- Plate, pipe or bar; dimensions and units.
- Quantity
- Number of pieces, length per piece or required weight.
- Tolerances
- Permitted dimensional variation, if specified.
- Finish and processing
- Surface finish, delivery condition and cutting requirements.
- Delivery
- Destination and preferred arrival date.
Add any inspection-document or packaging requirements. Theoretical weight is for planning; confirm the billing basis with the supplier.
Formula
Round tube area = π × [outside diameter² − (outside diameter − 2 × wall thickness)²] / 4.
Idealized square tube area = outside width² − (outside width − 2 × wall thickness)².
Idealized rectangular tube area = outside width × outside height − (outside width − 2 × wall thickness) × (outside height − 2 × wall thickness).
Theoretical mass = section area × length × nominal density × quantity.
Common examples
Load a calculated example, then adjust its dimensions or quantity.
| Example | Inputs | Calculated answer | Load example |
|---|---|---|---|
| Light structural frameHSS 2 × 2 × 0.125 inIdealized square-tube geometry gives an early estimate; use the applicable HSS table when design thickness and rounded corners matter. | Material or alloy: Carbon steel; Shape: Square tube; Outside width: 2 in; Wall thickness: 0.125 in; Length: 20 ft; Quantity: 12 | Total theoretical weight345.111568 kg | |
| Equipment skid frameHSS 4 × 2 × 0.188 inRectangular outside dimensions and wall thickness support an early skid takeoff, while structural design values come from the governing HSS data. | Material or alloy: Carbon steel; Shape: Rectangular tube; Outside width: 4 in; Outside height: 2 in; Wall thickness: 0.188 in; Length: 24 ft; Quantity: 8 | Total theoretical weight622.746627 kg | |
| Machine component stockRound steel tube, 2 in OD × 0.120 in wallGeneric round tube can be calculated from actual geometry, with specification, manufacturing route, machining allowance, and bore finishing recorded separately. | Material or alloy: Carbon steel; Shape: Round tube; Outside diameter: 2 in; Wall thickness: 0.12 in; Length: 12 ft; Quantity: 10 | Total theoretical weight130.45094 kg | |
| Metric workshop frameSquare tube, 50 × 50 × 3 mmStock-length planning can use the sharp-corner formula, although a supplier's catalog mass may account for corner radii and manufacturing tolerances. | Material or alloy: Carbon steel; Shape: Square tube; Outside width: 50 mm; Wall thickness: 3 mm; Length: 6 m; Quantity: 20 | Total theoretical weight527.904 kg | |
| Fabricated base frameRectangular tube, 100 × 50 × 4 mmBefore ordering a base frame, match tube length and piece count to the cut list, then add plates, welds, and hardware. | Material or alloy: Carbon steel; Shape: Rectangular tube; Outside width: 100 mm; Outside height: 50 mm; Wall thickness: 4 mm; Length: 12 m; Quantity: 6 | Total theoretical weight637.9776 kg | |
| Guard and frame fabricationRound tube, 60.3 × 3.2 mmExplicit outside diameter and wall thickness avoid the errors that arise when a pipe designation is treated as a measured tube size. | Material or alloy: Carbon steel; Shape: Round tube; Outside diameter: 60.3 mm; Wall thickness: 3.2 mm; Length: 6 m; Quantity: 14 | Total theoretical weight376.105642 kg | |
| Stainless steel 304Handrail material estimateRound tube, 42.4 × 2.6 mmHandrail takeoffs should add bends, posts, fittings, and finish after calculating the straight tube, with loading checked separately. | Material or alloy: Stainless steel 304; Shape: Round tube; Outside diameter: 42.4 mm; Wall thickness: 2.6 mm; Length: 6 m; Quantity: 18 | Total theoretical weight277.368501 kg | |
| Trailer fabrication takeoffSquare tube, 3 × 3 × 0.25 inMaterial weight helps with purchasing a trailer frame, but it is not a payload rating or structural approval. | Material or alloy: Carbon steel; Shape: Square tube; Outside width: 3 in; Wall thickness: 0.25 in; Length: 20 ft; Quantity: 10 | Total theoretical weight843.606055 kg | |
| Machine-base railRectangular tube, 6 × 4 × 0.25 inLong machine-base rails should be checked for stock availability, straightness tolerance, cut allowance, and handling requirements. | Material or alloy: Carbon steel; Shape: Rectangular tube; Outside width: 6 in; Outside height: 4 in; Wall thickness: 0.25 in; Length: 24 ft; Quantity: 4 | Total theoretical weight699.426111 kg | |
| Stainless steel 304Food-equipment frame304 stainless square tube, 40 × 40 × 2 mmFood-equipment frames also require confirmation of stainless grade, finish, weld seam, fabrication method, and cleanability. | Material or alloy: Stainless steel 304; Shape: Square tube; Outside width: 40 mm; Wall thickness: 2 mm; Length: 6 m; Quantity: 24 | Total theoretical weight345.8304 kg |
Frequently asked questions
What is the difference between pipe and tube for this calculation?
The geometry can be similar, but ordering conventions differ. Pipe is often designated by nominal size and schedule; tube is commonly specified by actual outside dimensions and wall thickness. Verify the applicable product convention.
Why can square tube catalog weight differ from the formula?
Real square and rectangular tube has rounded corners and may use a design thickness different from the nominal wall. Catalog or standard nominal mass should remain a separate value.
Can this result be used for structural design?
It can support an early material takeoff, but it does not provide section properties, design strength, tolerance effects, connection checks, or engineering approval.
Should I use nominal or measured wall thickness?
Use nominal product dimensions for a purchasing estimate and measured dimensions for an as-built check, but label the basis clearly and do not mix the two across items.
Sources
Circumference, Area and Volume (Opens in a new tab)
National Institute of Standards and Technology
- Supports
- Geometry or calculation formula
- Checked
NIST Guide to the SI, Appendix B.8 and footnotes (Opens in a new tab)
National Institute of Standards and Technology
- Supports
- Unit conversion
- Checked
Code of Standard Practice for Steel Buildings and Bridges (Opens in a new tab)
American Institute of Steel Construction
- Supports
- Material density
- Checked