Enter price per weight unit to estimate total cost.
Total Weight
0.00 kg
Weight per Piece
0.00 kg
Weight per Meter/Foot
0.00 kg/m
Total Surface Area
0.00 m²
Estimated Cost
$0.00
Formula: Volume × Density. Volume calculated as (Outer Area – Inner Area) × Length.
Cross-Section Visualization
Visual representation of the rectangular tube profile (not to scale).
Detailed Breakdown
Metric
Value
Unit
What is a Rect Tube Weight Calculator?
A rect tube weight calculator is an essential engineering and logistics tool designed to determine the mass of rectangular hollow sections (RHS). These structural elements are widely used in construction, manufacturing, and mechanical engineering due to their high strength-to-weight ratio.
This calculator helps engineers, fabricators, and procurement managers estimate the total load of materials before ordering. By inputting dimensions such as width, height, wall thickness, and length, users can instantly derive the weight for various materials including steel, aluminum, and stainless steel.
Common misconceptions include assuming that weight scales linearly with width alone, or ignoring the impact of corner radii on the final weight. While this calculator uses a geometric subtraction method for speed and standard estimation, it provides a highly accurate baseline for transport planning and cost estimation.
Rect Tube Weight Calculator Formula
The mathematical foundation for calculating the weight of a rectangular tube involves determining the volume of the material and multiplying it by the material's density. The formula derives from subtracting the volume of the inner void from the total outer volume.
The Formula:
Weight = [ (W × H) – (W – 2t) × (H – 2t) ] × L × ρ
Variable
Meaning
Metric Unit
Imperial Unit
W
Outer Width
mm
inches
H
Outer Height
mm
inches
t
Wall Thickness
mm
inches
L
Length
meters
feet
ρ (Rho)
Material Density
kg/m³
lb/ft³
Practical Examples
Example 1: Structural Steel Column
A construction project requires 10 steel columns. The specifications are:
Dimensions: 150mm x 100mm
Thickness: 5mm
Length: 6 meters
Material: Mild Steel (Density ~7850 kg/m³)
Using the rect tube weight calculator, we find that a single beam weighs approximately 115 kg. The total weight for 10 beams would be 1,150 kg. This calculation is vital for ensuring the delivery truck is not overloaded.
Example 2: Aluminum Frame
A lightweight frame is being built using 6061 Aluminum.
Dimensions: 2 inches x 1 inch
Thickness: 0.125 inches
Length: 10 feet
Material: Aluminum (Density ~168 lb/ft³)
The calculator indicates a weight of roughly 8.4 lbs per piece. This low weight confirms the material choice is appropriate for a portable structure.
How to Use This Rect Tube Weight Calculator
Select Unit System: Choose between Metric (mm/kg) or Imperial (in/lbs) based on your project specs.
Choose Material: Select the material type (e.g., Steel, Aluminum). This automatically sets the density. If you have a custom alloy, select "Custom" and enter the density manually.
Enter Dimensions: Input the outer Width, Height, and Wall Thickness. Ensure the thickness is not greater than half the width or height.
Set Length & Quantity: Enter the length of a single tube and the total number of pieces required.
Review Results: The tool updates in real-time, showing total weight, weight per meter, and surface area (useful for painting estimates).
Key Factors That Affect Results
Material Density: This is the most critical factor. Steel is roughly 3 times heavier than aluminum. Using the wrong density value will result in massive errors.
Wall Thickness Tolerances: Manufacturing tolerances mean the actual thickness might vary slightly from the nominal value (e.g., +/- 5%), affecting the actual weight.
Corner Radius: Real-world rectangular tubes have rounded corners. A purely geometric calculation (sharp corners) slightly overestimates weight. Engineering tables often account for this, but the difference is usually negligible for general logistics.
Galvanization/Coating: If the tube is galvanized, the zinc coating adds weight (typically 3-5%) which is not accounted for in the raw material calculation.
Temperature: While thermal expansion affects dimensions, it rarely impacts weight calculations significantly for standard construction projects.
Scrap/Cut Loss: When ordering, always account for the material lost during cutting (kerf width), though this affects cost more than the weight of the finished part.
Frequently Asked Questions (FAQ)
Does this calculator account for rounded corners?
This tool uses a geometric subtraction method (Outer Box – Inner Box). It does not subtract the mass lost at the rounded corners. For most logistics and cost estimation purposes, this provides a safe, slightly conservative estimate.
What is the density of mild steel?
Mild steel typically has a density of 7,850 kg/m³ or roughly 0.284 lb/in³. This is the default value used in our rect tube weight calculator.
Can I calculate the weight of a square tube?
Yes. Simply enter the same value for both Width and Height inputs.
Why is the wall thickness limited?
The wall thickness cannot exceed half of the width or height because that would mean the hole inside the tube disappears or overlaps, which is physically impossible.
How do I calculate painting area?
The calculator automatically provides the "Total Surface Area". This is calculated as the outer perimeter multiplied by the length. It does not include the interior surface area.
Is stainless steel heavier than regular steel?
Slightly. Stainless steel (304/316) has a density of around 7,900-8,000 kg/m³, while mild steel is around 7,850 kg/m³. The difference is small but can add up in large quantities.
How accurate is this for cost estimation?
It is very accurate for raw material weight. However, final cost depends on market rates, shipping fees, and processing charges (cutting, drilling).
What if my tube is hollow but not rectangular?
This specific tool is for rectangular or square profiles. For round tubes or solid bars, please use our specific calculators listed below.