Steel Flat Bar Weight Calculator
Calculate the weight of Steel Flat Bar by entering your dimensions. The density of Steel is 0.2833 lb/in³ (7842 kg/m³). Use this calculator for quick stock weight estimates in your CNC machining projects. Accurate weight calculations are essential for shipping quotes, material cost estimation, fixturing load analysis, and structural design verification. The theoretical weight formula assumes a uniform cross-section and standard alloy density; actual weights may differ slightly by grade and mill tolerance. Weight data is calculated using the standard volumetric formula multiplied by the material density constant shown above.
Material Properties
| Material | Steel |
| Shape | Flat Bar |
| Density | 0.2833 lb/in³ / 489.5 lb/ft³ / 7842 kg/m³ |
| Example Weight | 1.7 lb / 0.771 kg |
Compare Materials — Flat Bar
| Material | Weight (lb) | Weight (kg) |
|---|---|---|
| Aluminum | 0.585 | 0.265 |
| Titanium | 0.966 | 0.438 |
| Cast Iron | 1.56 | 0.708 |
| Steel (current) | 1.7 | 0.771 |
| Stainless Steel | 1.725 | 0.782 |
| Brass | 1.839 | 0.834 |
| Copper | 1.944 | 0.882 |
Sourcing and Use Notes
Carbon steel grades cover most general fabrication. A36 is hot-rolled structural plate and shape stock — economical but loose on dimensional tolerance and with mill scale that must be removed before painting. 1018 is cold-finished low-carbon bar with a clean surface and tighter size control, used for machine keys, shafts, and weldable fixtures. 4140 is a chromium-molybdenum alloy steel commonly stocked annealed (around 200 HB) and capable of being heat-treated to 30–40 HRC for shafts, gears, and dies that need toughness with wear resistance.
Rectangular flat bar is the go-to stock for brackets, fabricated frames, machine slides, gibs, knife edges, and electrical bus bars. Standard hot-rolled flat bar holds about ±1.5% on cross-section per ASTM A6 — fine for weldments but loose for machine-fit features, so over-size for finishing operations. Cold-finished flat bar (1018 or 12L14 in steel; 6061-T6511 in aluminum) holds tighter tolerances and presents a clean machinable surface. Edges are roll-formed with a small radius; specify '90-degree cut edge' if a sharp corner is critical.
Common Applications
Steel Flat Bar is a standard stock form used in structural frames, machine bases, brackets, and fabricated components. Its consistent cross-section simplifies weight-per-foot calculations and material takeoffs for procurement and shipping cost estimates. Engineers and machinists rely on theoretical weight data during the quoting and planning stages before final parts are produced. For large orders or weight-critical designs, request certified mill test reports (MTRs) to confirm actual density and alloy composition.
Sourcing and Weight Tolerance Note
This weight is based on the theoretical density of Steel. Mill tolerances (ASTM A6 allows ±2.5% on cross-sectional area for structural shapes) and surface treatments (anodizing, plating, painting) may add 1–3% to actual shipped weight. Order 5–10% material overage to account for saw kerfs and offcuts. Always verify actual material density with your supplier's material test report (MTR) for critical structural or load-bearing applications. Compare weights across materials using the comparison table above to make informed material selection decisions for your project.