Metal Weight Calculator

The metal weight calculator finds the cross-sectional area of round bar, square bar, flat bar or round tube, then multiplies by 12 (inches per foot) and the material's density. It returns the weight per foot and the total weight. A 1 in. round steel bar weighs about 2.67 lb per foot.

Last reviewed September 2026Method & sources Report an error

Not to scale.

Total Weight

26.7 lb

Breakdown
Total Weight	26.7 lb
Weight per Foot	2.673 lb/ft

How to Calculate Metal Weight

Weight comes directly from each shape's cross-sectional area, not a lookup table. A round bar's area is `π × radius²`, a square bar's is `side²`, and a flat bar's is `width × thickness`. A round tube's is the ring area between its outer and inner diameters (`π × (outer radius² − inner radius²)`, with inner diameter found by subtracting twice the wall thickness). Multiplying that area by 12 in./ft and the material's density gives weight per foot. Multiplying by length gives the total. This is the same geometry-driven approach the Pipe Weight calculator uses for pipe schedules.

Example: 1 in. diameter round steel bar, 10 ft long

A 1 in. diameter round steel bar, 10 ft long: 1. Cross-sectional area: π × (1 ÷ 2)² = π × 0.25 ≈ 0.7854 sq in. 2. Weight per foot: 0.7854 × 12 × 0.2836 ≈ 2.673 lb/ft. 3. Total weight: 2.673 × 10 ≈ 26.7 lb. Each foot of this bar weighs about 2.67 lb, so the 10 ft length comes to about 26.7 lb.

Metal Weight: Compare Scenarios

Scenario	Total Weight	Weight per Foot
Small (2 ft offcut)	5.3 lb	2.673 lb/ft
Medium (10 ft stock length)	26.7 lb	2.673 lb/ft
Large (25 ft mill length)	66.8 lb	2.673 lb/ft

What Is Metal Weight?

A metal weight calculator converts a bar, plate, or tube's shape, dimensions, and material into its total weight. It's useful for estimating shipping cost, checking what a support structure needs to carry, or comparing stock options before ordering.

Metal Weight: Pros and Cons

Pros

Computes weight from real cross-sectional geometry rather than a static per-size lookup table. It works for any dimension you enter, not only a preset list of standard sizes
Covers four common stock shapes (round bar, square bar, flat bar/plate, round tube) in one calculator
Material density is a swappable constant, so steel, aluminum, and stainless steel are all handled with the same formula

Cons

Doesn't cover angle, channel, or square/rectangular tube shapes, which need a different cross-section formula than the four covered here
Assumes a solid bar or a uniform-wall round tube. A shape with a more complex profile (like an I-beam) isn't covered
Material densities used here are standard reference figures for common alloys. A specific alloy grade can vary slightly from these baseline values

Metal Weight: What a Pro Checks

This covers round bar, square bar, flat bar, and round tube only. Angle, channel, and square/rectangular tube need a different cross-section formula, not this one.
Check your specific alloy's published density if you need a precise weight. The values here are standard reference figures for common alloys, and a specific grade can run slightly different.
Switching from steel to aluminum at the same dimensions cuts weight to roughly a third. Aluminum's density is about 34% of steel's, which makes it useful for a quick materials comparison before ordering.

Frequently Asked Questions

How much does a steel round bar weigh?

It depends on diameter and length. A 1 in. diameter steel round bar weighs about 2.67 lb per foot, found from its cross-sectional area (π × radius²) times 12 in./ft times steel's density (0.2836 lb/cu in).

How do you calculate the weight of a metal plate?

Multiply width by thickness to get the cross-sectional area, then by 12 in./ft and the material's density to get weight per foot, then by the plate's length for the total weight.

How much lighter is aluminum than steel at the same size?

About a third the weight. Aluminum's density (0.0975 lb/cu in) is roughly 34% of steel's (0.2836 lb/cu in). So the same bar or tube shape in aluminum weighs about a third as much as the steel version.

How do you calculate the weight of a hollow tube?

Find the ring-shaped cross-sectional area between the outer and inner diameters (π × (outer radius² − inner radius²)), where inner diameter is outer diameter minus twice the wall thickness. Then multiply by length and density the same way as a solid bar.

What's the difference between this and the Pipe Weight calculator?

The Pipe Weight calculator uses standard NPS pipe schedule dimensions (fixed outside diameters and wall thicknesses by nominal size). This calculator is for general bar, plate, and tube stock where you enter the exact dimensions directly, rather than picking a standard pipe schedule.

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