⚖️ Metal Weight Calculator

Knowing the weight of a metal part before it is cut is one of the most useful habits in any workshop, fabrication shop or purchasing department. The metal weight calculator uses the simple relationship weight = volume × density. For a round bar the volume is πr²L, for a hollow pipe it is the ring area times the length, for a flat plate it is length × width × thickness, and for a square bar the cross-section is side × side. Pick the shape, enter the dimensions, choose the material, and the weight is returned instantly in kilograms or pounds.

Steel is by far the most common material, with a density around 7,850 kg/m³. Aluminum is roughly one third of that at 2,700 kg/m³, which is why aluminum ladders and frames are so much easier to lift. The calculator ships with a density table covering steel, stainless steel, aluminum, copper, brass, bronze, cast iron and titanium, and you can also type a custom density for alloys or plastics.

For each shape the calculator computes the cross-sectional area, multiplies by the length to get volume, then multiplies by density. In metric mode dimensions are entered in millimetres and the density in g/cm³, and the result is given in kilograms. In imperial mode dimensions are in inches and the result in pounds.

The per-meter weight is a derived metric that estimators use constantly: a 12 mm round steel bar weighs about 0.89 kg per meter, so a 6 meter length is roughly 5.3 kg. Knowing this number makes it easy to price stock, plan lifting equipment, and compare material costs before buying. You can cross-check shipping estimates with our weight converter or volume calculator.

1. Choose the shape: round bar, pipe, flat plate, or square bar.
2. Enter the dimensions in the selected unit system (mm or inches).
3. Choose a material from the density table, or enter a custom density.
4. Click Calculate to see the total weight and weight per meter.
5. Switch between kg and lb if you need the result in imperial units.

Why does my pipe weight not match the catalog?

Catalog weights are usually calculated from the nominal wall thickness, while real pipes are rolled slightly thicker or thinner within tolerance. Measure the actual wall thickness and outside diameter with calipers for the most accurate result.

Is stainless steel heavier than mild steel?

Slightly. Stainless 304 has a density of about 8.00 g/cm³ versus 7.85 g/cm³ for mild steel, roughly a 2% difference. Over a long bar or large plate this adds up in both weight and cost.

Can I calculate the weight of a hollow square tube?

This version covers round bars, pipes, plates and solid square bars. For a square tube, subtract the inner square area from the outer square area, multiply by length and density, then enter the result as a custom shape or use a rectangular hollow section formula manually.

What is the difference between brass and bronze?

Brass is a copper-zinc alloy (typically 8.5 g/cm³) used for valves and fittings; bronze is a copper-tin alloy (typically 8.7–8.9 g/cm³) used for bearings and marine hardware. Their densities are close, so weight differences for small parts are minor.

How do I convert the result to ounces or tons?

1 kg = 35.27 oz and 1 tonne (metric) = 1,000 kg. A short ton is 2,000 lb, a long ton is 2,240 lb. Most fabrication quotes use kg or lb, so the calculator's default units cover the common cases.

Does the calculator account for coating or plating?

No. Zinc plating, powder coating or paint add a very thin layer that changes weight by fractions of a percent. For precision work weigh a sample after coating and add the difference as a custom density adjustment.

Use the material density at room temperature; densities of metals change only slightly with temperature and can be ignored for shop-floor work. Mild steel and stainless steel look similar but differ by about 2%, which matters when you order large quantities. Always measure the actual dimensions of stock, especially pipes—nominal pipe sizes (such as 1 inch) are not the true outside diameter. The per-meter weight output is handy for estimating shipping cost; compare against your courier's published rates. For hollow sections the wall thickness is the difference between the outer and inner radius, so measure the wall directly with calipers rather than subtracting diameters.