Aluminum 7075-T6 Square Tube Weight
Mass per metre and per foot for aluminum 7075-t6 square tube at 2,810 kg/m³ (ASTM B211 / B209 (T6 temper)). Every figure is for the section as drawn. A 6 m length of this size weighs 7.5 kg (16.8 lb per 20 ft).
At the reference dimensions (a = 40 mm, t = 3 mm) this section has a cross-sectional area of 444.0 mm², giving 1.248 kg/m (0.838 lb/ft). Against carbon steel's 7,850 kg/m³ that is -64.2 % — the same section in steel would be 3.485 kg/m.
Square Tube — formula and derivation
Area of a square tube
A = a² − (a − 2t)²
A = a² − (a − 2t)², which expands to A = 4t(a − t)
Worked through with the default dimensions:
A = a² − (a − 2t)²Inner side = 40 − 2 × 3 = 34.0 mmA = 40² − 34.0²A = 1600.0 − 1156.0A = 444.0 mm²
- a
- Side
- t
- Wall thickness
Weight follows from the area with no further geometry: m = A × 10⁻⁶ × ρ, where A is in mm², ρ in kg/m³ and m in kg/m. At 2,810 kg/m³ that is 1.2476 kg/m for the reference size above.
AL 7075 square tube — size series
| Side | 1.5 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
|---|---|---|---|---|---|---|
| 15 mm | 0.228 kg/m · 0.153 lb/ft | 0.292 kg/m · 0.196 lb/ft | 0.405 kg/m · 0.272 lb/ft | 0.495 kg/m · 0.332 lb/ft | 0.562 kg/m · 0.378 lb/ft | 0.607 kg/m · 0.408 lb/ft |
| 20 mm | 0.312 kg/m · 0.210 lb/ft | 0.405 kg/m · 0.272 lb/ft | 0.573 kg/m · 0.385 lb/ft | 0.719 kg/m · 0.483 lb/ft | 0.843 kg/m · 0.566 lb/ft | 0.944 kg/m · 0.634 lb/ft |
| 25 mm | 0.396 kg/m · 0.266 lb/ft | 0.517 kg/m · 0.347 lb/ft | 0.742 kg/m · 0.498 lb/ft | 0.944 kg/m · 0.634 lb/ft | 1.124 kg/m · 0.755 lb/ft | 1.281 kg/m · 0.861 lb/ft |
| 30 mm | 0.481 kg/m · 0.323 lb/ft | 0.629 kg/m · 0.423 lb/ft | 0.910 kg/m · 0.612 lb/ft | 1.169 kg/m · 0.786 lb/ft | 1.405 kg/m · 0.944 lb/ft | 1.619 kg/m · 1.088 lb/ft |
| 40 mm | 0.649 kg/m · 0.436 lb/ft | 0.854 kg/m · 0.574 lb/ft | 1.248 kg/m · 0.838 lb/ft | 1.619 kg/m · 1.088 lb/ft | 1.967 kg/m · 1.322 lb/ft | 2.293 kg/m · 1.541 lb/ft |
| 50 mm | 0.818 kg/m · 0.549 lb/ft | 1.079 kg/m · 0.725 lb/ft | 1.585 kg/m · 1.065 lb/ft | 2.068 kg/m · 1.390 lb/ft | 2.529 kg/m · 1.699 lb/ft | 2.967 kg/m · 1.994 lb/ft |
| 60 mm | 0.986 kg/m · 0.663 lb/ft | 1.304 kg/m · 0.876 lb/ft | 1.922 kg/m · 1.292 lb/ft | 2.518 kg/m · 1.692 lb/ft | 3.091 kg/m · 2.077 lb/ft | 3.642 kg/m · 2.447 lb/ft |
| 80 mm | 1.324 kg/m · 0.889 lb/ft | 1.753 kg/m · 1.178 lb/ft | 2.596 kg/m · 1.745 lb/ft | 3.417 kg/m · 2.296 lb/ft | 4.215 kg/m · 2.832 lb/ft | 4.991 kg/m · 3.354 lb/ft |
| 100 mm | 1.661 kg/m · 1.116 lb/ft | 2.203 kg/m · 1.480 lb/ft | 3.271 kg/m · 2.198 lb/ft | 4.316 kg/m · 2.900 lb/ft | 5.339 kg/m · 3.588 lb/ft | 6.339 kg/m · 4.260 lb/ft |
Rows: side (mm). Columns: wall thickness (mm). Computed for Aluminum 7075-T6 at 2810 kg/m³.
| Side | 1.5 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 |
|---|---|---|---|---|---|---|
| 15 mm | 81.0 | 104.0 | 144.0 | 176.0 | 200.0 | 216.0 |
| 20 mm | 111.0 | 144.0 | 204.0 | 256.0 | 300.0 | 336.0 |
| 25 mm | 141.0 | 184.0 | 264.0 | 336.0 | 400.0 | 456.0 |
| 30 mm | 171.0 | 224.0 | 324.0 | 416.0 | 500.0 | 576.0 |
| 40 mm | 231.0 | 304.0 | 444.0 | 576.0 | 700.0 | 816.0 |
| 50 mm | 291.0 | 384.0 | 564.0 | 736.0 | 900.0 | 1,056.0 |
| 60 mm | 351.0 | 464.0 | 684.0 | 896.0 | 1,100.0 | 1,296.0 |
| 80 mm | 471.0 | 624.0 | 924.0 | 1,216.0 | 1,500.0 | 1,776.0 |
| 100 mm | 591.0 | 784.0 | 1,164.0 | 1,536.0 | 1,900.0 | 2,256.0 |
Area is a property of the geometry alone, so this table is the same for every material. It is what you enter into a stress calculation; the mass table is what you enter into an order.
Each row is one nominal size. Because the area is computed from your dimensions rather than read from a mill table, a non-standard size is just as accurate — put it into the calculator above rather than interpolating between rows.
The same square tube in every material
Geometry is fixed and only density changes, so this table is the whole material-selection question in one view. Aluminum 7075-T6 is highlighted. The percentage column is against carbon steel, which is the figure most quotations are built on.
| Material | Density kg/m³ | lb/in³ | Mass / length kg/m | lb/ft | vs carbon steel |
|---|---|---|---|---|---|
| Carbon Steel | 7,850 | 0.2836 | 3.485 | 2.342 | +0.0 % |
| Stainless Steel 304 | 8,000 | 0.2890 | 3.552 | 2.387 | +1.9 % |
| Stainless Steel 316 | 8,000 | 0.2890 | 3.552 | 2.387 | +1.9 % |
| Stainless Steel 316L | 8,000 | 0.2890 | 3.552 | 2.387 | +1.9 % |
| Stainless Steel 430 | 7,700 | 0.2782 | 3.419 | 2.297 | -1.9 % |
| Aluminum 6061-T6 | 2,700 | 0.0975 | 1.199 | 0.806 | -65.6 % |
| Aluminum 5052-H32 | 2,680 | 0.0968 | 1.190 | 0.800 | -65.9 % |
| Aluminum 7075-T6 | 2,810 | 0.1015 | 1.248 | 0.838 | -64.2 % |
| Copper C11000 | 8,940 | 0.3230 | 3.969 | 2.667 | +13.9 % |
| Brass C36000 | 8,500 | 0.3071 | 3.774 | 2.536 | +8.3 % |
| Bronze C93200 | 8,800 | 0.3179 | 3.907 | 2.626 | +12.1 % |
| Titanium Grade 2 | 4,510 | 0.1629 | 2.002 | 1.346 | -42.5 % |
| Gray Cast Iron | 7,200 | 0.2601 | 3.197 | 2.148 | -8.3 % |
| Lead | 11,340 | 0.4097 | 5.035 | 3.383 | +44.5 % |
| Rigid PVC (Type I) | 1,400 | 0.0506 | 0.622 | 0.418 | -82.2 % |
| HDPE (PE 100) | 960 | 0.0347 | 0.426 | 0.286 | -87.8 % |
Same geometry throughout, so the only variable is density. Carbon steel is highlighted as the baseline.
A note on using this table for costing: mass is not price. Aluminium is roughly a third of steel's mass here, but per kilogram it costs several times more, so a straight swap rarely saves money — what it buys is reduced load on a structure or a vehicle.
About aluminum 7075-t6
Zinc-bearing, aerospace-grade and the strongest aluminium in ordinary supply — comparable in strength to some mild steels. It is also the densest aluminium here at 2,810 kg/m³, which is the trade-off nobody mentions: choosing 7075 over 6061 for strength costs 4.1 % more mass for the same volume. Its corrosion resistance is poor without cladding or anodising, and it is generally considered unweldable, so it belongs in machined and riveted parts, not fabricated frames.
- Density
- 2,810 kg/m³ = 0.1015 lb/in³ · 0.3580× carbon steel · typical spread ±1 %
- Specification
- ASTM B211 / B209 (T6 temper)
- Equivalents
- EN AW-7075 · JIS A7075 · GB 7075
- Typical uses
- Aerospace structural parts · High-load bicycle and motorsport · Moulds and tooling plate · Precision machined fittings
Not recommended for sustained elevated-temperature service; strength falls off well before 6061’s does.
About square tube
Square tube expands cleanly to A = 4t(a − t), which makes the sensitivity obvious: for a given side, weight is almost exactly linear in wall thickness. Doubling a 2 mm wall to 4 mm adds about 1.9 times the mass, not twice, because the inner void shrinks as the wall grows. Its flat faces also make it the natural choice for welded frames and for anything that has to be drilled, tapped or bolted through a face — a round tube gives you only a tangent point where a square tube gives you a full flat.
Specified as side × wall thickness. Corner radii are standardised per EN 10219 and change the area slightly at heavier walls.
Download this data
AL 7075 square tube — CSV
Both buttons below read the tables rendered on this page, so the file matches what you are looking at. The full catalogue — all 16 materials across all 10 sections — is on the downloads page.
Fields are quoted per RFC 4180, with a UTF-8 byte-order mark so Excel reads the mm² and · characters correctly. Blank lines separate the weight matrix from the area matrix.
Frequently asked questions
How much does aluminum 7075-t6 square tube weigh?
At the reference dimensions (a = 40 mm, t = 3 mm) a aluminum 7075-t6 square tube of this size weighs 1.248 kg/m, or 0.838 lb/ft. The table above lists the figure for every standard size so you can read your size directly instead of scaling.
How is the weight of square tube calculated?
Weight is cross-sectional area × length × density. For this shape the area is A = a² − (a − 2t)². At the reference dimensions that gives 444.0 mm², and multiplying by aluminum 7075-t6's density of 2,810 kg/m³ gives 1.248 kg/m. Nothing is looked up in a table — which is why a non-standard size is calculated just as accurately as a standard one.
Why does aluminum 7075-t6 weigh more or less than steel?
It is lighter than carbon steel for the same section — about 64 % lighter at 2,810 kg/m³. Density is the only variable: the cross-sectional area depends purely on geometry, so a square tube of the same dimensions has the same area in every material and the mass simply scales with density. In this case the ratio is 0.3580× carbon steel.
What is the cross-sectional area of a square tube?
The area depends only on the dimensions, not on the material, so it is identical whichever material you select: at the reference dimensions it is 444.0 mm² (0.6882 in²). That is the number you would enter into a stress or deflection calculation, and it is why changing material on this page never changes the area column.
Does a al 7075 square tube weigh the same as a al 7075 part of a different shape?
No, and the difference is larger than most people expect. At equal nominal size, a square bar is 27.3 % heavier than a round bar, and a hollow section is typically 60–80 % lighter than the solid bar it replaces. Weight follows area, and area changes faster than dimensions do — which is exactly why this needs calculating rather than estimating.
Should I use AL 7075 weight or carbon steel weight for costing?
Use the material you are actually buying. At 2,810 kg/m³ against carbon steel's 7,850 kg/m³, the same square tube differs by 64.2 % in mass. On a per-metre quote that is invisible; on a fabricated tonnage it is the difference between a margin and a loss. This page computes the steel figure as 3.485 kg/m for comparison.
Other materials, same square tube
The same geometry in every material, so the only variable is density.
- Carbon steel square tube — 7850 kg/m³
- SS 304 square tube — 8000 kg/m³
- SS 316 square tube — 8000 kg/m³
- AL 6061 square tube — 2700 kg/m³
- Copper square tube — 8940 kg/m³
- Brass square tube — 8500 kg/m³
- HDPE square tube — 960 kg/m³
- PVC square tube — 1400 kg/m³
Other AL 7075 sections
The same density applied to every shape the site covers.
- AL 7075 round bar — A = π/4 · d²
- AL 7075 square bar — A = a²
- AL 7075 hexagonal bar — A = (√3/2) · AF² ≈ 0.8660 · AF²
- AL 7075 flat bar — A = w · t
- AL 7075 plate — A = w · t
- AL 7075 round tube — A = π/4 · (D² − d²), d = D − 2t
Reference data and tools
- Metal weight overview — how the calculation works
- All 16 materials — densities and specifications
- All 10 sections — formulas and size series
- Density chart — lightest to heaviest
- Metal weight calculator — any size, any material
- All calculators — metal weight and pipe weight
- Download the data — CSV, generated from the same source
- Cross-reference tables — DN / NPS / material equivalents
- Methodology and sources — where every number comes from
Square Tube area from A = a² − (a − 2t)². Mass computed as area × length × density at 2,810 kg/m³ (ASTM B211 / B209 (T6 temper)). No weight on this page is copied from a published table — which is why figures can differ in the last significant digit from a mill's chart calculated at a nominal density.
- Elementary plane geometry. The circle, polygon and hollow-section area formulas.
- ASTM material specifications for each grade named in the material entry (A36, A240/A276, B209/B211/B221, B152/B16/B505, B265/B348, A48, B29, D1784, D3350).
- BIPM / NIST definitional constants: international inch = 25.4 mm, foot = 0.3048 m, pound = 0.45359237 kg.
Dataset version 2026.09.1 · dimensions last verified against source 2026-09-21. Found an error? Report it — corrections are issued with a version bump.