How to calculate metal weight?

Metal weight = Volume × Density. Calculate the cross-section area based on the shape (round, pipe, flat, etc.), multiply by the length to get volume, then multiply by the material density. Weight (kg) = Volume (mm³) × Density (kg/m³) / 1,000,000,000.

What is the density of steel?

Mild/carbon steel density is approximately 7,850 kg/m³ (0.283 lb/in³). Stainless steel is slightly higher at ~7,900 kg/m³. These values are used for weight calculations of structural steel profiles.

What is the difference between pipe and tube?

Pipe is specified by nominal bore (NB/DN) and schedule, while tube is specified by outside diameter and wall thickness. In weight calculations, the formula is the same: π/4 × (OD² − ID²) × Length. The difference is only in how dimensions are specified.

How to calculate weight per meter?

Weight per meter = Cross-section area (mm²) × Density (kg/m³) / 1,000,000. For example, a Ø50 mm round steel bar: Area = π/4 × 50² = 1,963.5 mm². Weight/m = 1,963.5 × 7,850 / 1,000,000 = 15.41 kg/m.

Free Engineering Tool

Metal Weight Calculator

Calculate the weight of metal profiles — round bar, pipe, flat bar, square, hex, angle, and channel. Select shape, enter dimensions, and get instant results.

7 Shapes 8 Materials kg / lb

Shape / Profile

Material / Density

Length (mm)

Quick presets

Results

Weight

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Weight (lb)

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Weight per meter

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Volume

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Cross-Section Area

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General Formula

Weight is calculated as:

Weight = Volume × Density / 10⁹ [kg]

Where all dimensions are in mm and density is in kg/m³. The factor 10⁹ converts mm³ to m³.

Cross-Section Formulas

Shape	Volume Formula (mm³)
Round bar	V = π/4 × d² × L
Pipe / Tube	V = π/4 × (OD² − ID²) × L (ID = OD − 2t)
Flat bar / Plate	V = width × thickness × L
Square bar	V = side² × L
Hex bar	V = (3√3 / 2) × s² × L (s = flat-to-flat)
Angle (L-profile)	V = (a × tₐ + (b − tₐ) × t_b) × L
Channel (U-profile)	V = (h × t_w + 2 × (b − t_w) × t_f) × L

Material Densities

Material	Density (kg/m³)	Density (lb/in³)
Carbon / Mild Steel	7 850	0.283
Stainless Steel	7 900	0.285
Aluminum	2 700	0.098
Copper	8 900	0.322
Brass	8 500	0.307
Titanium	4 510	0.163
Cast Iron	7 200	0.260

Practical Example

Example — Ø50 mm Round Steel Bar, 1 meter long

Given: d = 50 mm, L = 1000 mm, Density = 7850 kg/m³

Area = π/4 × 50² = 1 963.5 mm²

Volume = 1 963.5 × 1000 = 1 963 495 mm³

Weight = 1 963 495 × 7850 / 10⁹ = 15.41 kg

Weight per meter = 15.41 kg/m

Tip: For pipes, you can enter either the wall thickness t or the inner diameter (ID) directly. If wall thickness is provided, the calculator computes ID = OD − 2×t automatically.

Metal Weight Calculator | Pipe, Round Bar, Flat, Sheet, Angle

Published by Nikolai Shelkovenko on February 15, 2026 February 15, 2026