Steel Bar Stock Weight Calculator
Quick answer
Enter a round, square, flat or hex bar's size and length and this tool gives the weight per piece, per foot and for a full quantity, in pounds and kilograms. Mild steel weighs about 0.2836 lb per cubic inch - so a 1/2 in round bar is roughly 0.67 lb/ft. Handy for buying stock and planning projects.
Stock weight
Round bar 0.500 in, 36.0 in long, x1. Mild steel at 0.2836 lb/in³.
| Size | Round | Square | Flat (x 1/4 in) |
|---|---|---|---|
| 1/4 in | 0.17 | 0.21 | 0.21 |
| 3/8 in | 0.38 | 0.48 | 0.32 |
| 1/2 in | 0.67 | 0.85 | 0.43 |
| 5/8 in | 1.04 | 1.33 | 0.53 |
| 3/4 in | 1.50 | 1.91 | 0.64 |
| 1 in | 2.67 | 3.40 | 0.85 |
Why bar weight matters to a blacksmith
Steel is sold and shipped by weight, so knowing what a bar weighs tells you what you will pay and whether you can carry it. It also helps you plan a project: estimate the stock a hook, a set of tongs or a knife needs, and buy the right length instead of guessing.
The math is simple: cross-sectional area x length x steel density (about 0.2836 lb per cubic inch, ~7.85 g/cm³). This assumes mild steel; high-carbon knife steels are within a percent or two. Planning a build? See beginner blacksmith projects for stock sizes, and the bar weight reference chart for quick lookups.
Frequently asked questions
How much does steel bar weigh?
It depends on the cross-section and length. A 1/2 inch round mild-steel bar weighs about 0.67 lb per foot; a 1 inch round about 2.67 lb per foot. Square bar of the same size weighs more (it has more area), and flat bar depends on width times thickness. Enter your dimensions above for an exact figure.
What is the density of steel?
Mild and carbon steel is about 0.2836 pounds per cubic inch, or roughly 7.85 grams per cubic centimetre (490 lb per cubic foot). Alloy and stainless steels vary by a percent or two. This calculator uses the mild-steel figure, which is close enough for buying stock and planning blacksmithing projects.
Does bar weight change with steel grade?
Only slightly. Plain carbon knife steels like 1084 and 5160 have nearly the same density as mild steel, so the weight is within about 1-2% - close enough for planning. Big differences only show up with very different materials such as aluminium or stainless, which this tool does not cover.