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Metal Weight Calculator

Weigh metal bar, pipe, tube, sheet & hex from size

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How to use

  1. 1.Choose the profile shape (round bar, square bar, round tube/pipe, rectangular sheet, or hexagon bar) and the metal, then pick metric (mm → kg) or imperial (in → lb) units.
  2. 2.Enter the dimensions the shape asks for — for example diameter and length for a bar, or outer diameter, wall thickness and length for a pipe.
  3. 3.Read the weight instantly, along with the cross-section area, volume, and the density used in the calculation.

About Metal Weight Calculator

A metal weight calculator tells you how much a bar, tube, plate, or sheet weighs before you cut or ship it, using one simple law of physics: weight = volume × density. You pick the profile shape, type its dimensions, choose the metal, and the tool multiplies the cross-section area by the length to get volume, then multiplies by the material density to get weight — instantly and entirely in your browser, with nothing uploaded.

Each shape has its own cross-section formula, and the calculator applies the right one automatically. A round bar is π·r² where r is the diameter divided by two. A square bar is s². A round tube or pipe is π·(R² − r²), the outer disk minus the bore, where R is the outer radius and r = R − wall thickness. A rectangular sheet or plate is simply length × width × thickness. A hexagon bar is (√3/2)·F², where F is the distance across flats — the wrench size that hex stock is actually sold by. Cross-section area is then multiplied by length to give volume, and volume by density to give weight.

Density is the other half of the equation, and it depends entirely on the metal. Common engineering values in kilograms per cubic meter are steel ≈ 7850, stainless steel (304) ≈ 8000, aluminum ≈ 2700, copper ≈ 8960, brass ≈ 8500, and titanium ≈ 4500. These are typical figures — real density shifts with the exact alloy, grade, and temper, so a mill certificate is the final word, but these values put you within a percent or two for estimating.

Units are kept clean to avoid the classic dimensional-error trap. In metric mode you enter every dimension in millimeters and read the weight in kilograms; in imperial mode you enter inches and read pounds. Internally the tool converts everything to SI meters and kilograms first, then converts the answer back to your chosen unit, so a steel round bar 20 mm across and 1000 mm long correctly returns about 2.47 kg, and the same math holds for pounds.

Who needs this? Fabricators and machinists estimate stock weight for quoting and cutting lists. Buyers and sellers price metal by the kilogram or pound. Logistics and shipping teams need weights for freight, crating, and load limits. Structural and mechanical engineers trade strength against mass when choosing between steel, aluminum, and titanium. Welders and hobbyists check whether a part will fit a rack or a mailer. Because the tool covers round bar, square bar, round pipe, hex bar, and flat sheet across six common metals, it replaces a stack of one-off spreadsheets. Everything runs client-side, so your dimensions never leave your device, and the result updates the moment you change a number — no Run button, no upload, no waiting.

Frequently asked questions

How do I calculate the weight of a metal bar or pipe?
Weight = volume × density. First find the cross-section area (π·r² for a round bar, π·(R²−r²) for a pipe), multiply by length to get volume, then multiply by the metal's density. This calculator does all three steps for you once you enter the size and material.
How do I find steel pipe weight?
Pick 'Round tube / pipe' and steel, then enter the outer diameter, wall thickness, and length. The tool computes the ring cross-section π·((OD/2)² − (OD/2 − wall)²), multiplies by length for volume, and by steel's density (7850 kg/m³) for weight. A 50 mm OD, 5 mm wall, 1000 mm steel pipe weighs about 5.55 kg.
What density does the calculator use for each metal?
Typical engineering values in kg/m³: steel 7850, stainless steel (304) 8000, aluminum 2700, copper 8960, brass 8500, titanium 4500. These are common reference figures — actual density varies with the specific alloy, grade, and temper, so use your material certificate when you need exact numbers rather than a close estimate.
How is a hexagon bar measured?
Hex bar is sized by the distance across flats (A/F) — the wrench size between two parallel faces, not the corner-to-corner distance. The cross-section area is (√3/2)·F², so a bar with a 24 mm across-flats measure has an area of about 499 mm². Enter that across-flats value, not the side length.
Why does my result differ slightly from the actual weight?
Two reasons. First, density is quoted for a typical alloy and can vary a few percent by grade and temper. Second, real bars and sheets carry mill tolerances (±) on every dimension. The tool gives the theoretical weight of a nominal piece, which is ideal for quoting and estimating but not a substitute for weighing the finished part.

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