Steel Weight Calculator
Estimate the weight of steel stock — sheet/plate, bar, tube, and more. Pick a profile, enter the dimensions in inches (length in feet), choose a grade (or type a custom density), and get total weight in pounds and kilograms, weight per piece, weight per foot, and cost — with a weight-by-grade comparison and a downloadable PDF.
| Grade | Density | Per foot | Total weight |
|---|---|---|---|
| Enter a size to compare grades | |||
| Pieces | Total weight | Kilograms | Cost |
|---|---|---|---|
| Enter a size to compare | |||
How to use the steel weight calculator
Pick a profile — sheet, round bar, tube, square bar, flat bar or hex bar — enter its dimensions and quantity, choose a steel grade, and get the total weight in pounds and kilograms, the weight per piece, the weight per foot and the cost, with a by-grade comparison table and a downloadable PDF.
Choose the profile
Sheet, round bar, tube, square bar, flat bar or hex — this sets which dimensions you enter.
Enter size & quantity
Dimensions in inches and length in feet, plus how many identical pieces.
Pick the grade
A36, 304/316 stainless, 4140, tool or spring steel — or type a custom density.
Read the result & save a PDF
See total, per-piece and per-foot weight, compare grades, and download it.
How steel weight is calculated
Every profile uses the same core idea: cross-section × length × density. Only the area formula changes from shape to shape, and the grade sets the density — which barely moves between steels.
Worked example — 2″ round bar, 8 ft long, A36 carbon steel
Area: π ÷ 4 × 2² = 3.14 in² = 0.0218 ft²
Weight per ft: 0.0218 × 490 = 10.7 lb/ft
Weight per piece: 10.7 × 8 = 85.5 lb
In kilograms: 85.5 × 0.4536 = 38.8 kg
An 8-foot length of 2-inch A36 round bar weighs about 85.5 lb (38.8 kg) — roughly 10.7 lb for every foot.
Steel weight reference charts
The numbers that come up most — weight per foot for round and square bar, weight per square foot for sheet, and how steel grades compare by density.
| Size | Round bar | Square bar | 8 ft round |
|---|---|---|---|
| 1/2 in | 0.67 lb/ft | 0.85 lb/ft | 5.3 lb |
| 3/4 in | 1.50 lb/ft | 1.91 lb/ft | 12.0 lb |
| 1 in | 2.67 lb/ft | 3.40 lb/ft | 21.4 lb |
| 1-1/2 in | 6.01 lb/ft | 7.65 lb/ft | 48.1 lb |
| 2 in | 10.7 lb/ft | 13.6 lb/ft | 85.5 lb |
| 3 in | 24.0 lb/ft | 30.6 lb/ft | 192 lb |
Round bar is about 2.67 lb/ft per inch of diameter squared; a square bar of the same side weighs about 27% more because it fills the corners. Weight rises with the square of the size.
| Thickness | Nominal | Per ft² | 4×8 sheet (32 ft²) |
|---|---|---|---|
| 1/8 in | 3 mm | 5.10 lb | 163 lb |
| 3/16 in | 5 mm | 7.66 lb | 245 lb |
| 1/4 in | 6 mm | 10.21 lb | 327 lb |
| 3/8 in | 10 mm | 15.31 lb | 490 lb |
| 1/2 in | 13 mm | 20.42 lb | 653 lb |
| 1 in | 25 mm | 40.83 lb | 1,307 lb |
Sheet runs about 40.8 lb per square foot per inch of thickness. Weight scales straight with thickness — double it and the sheet weighs twice as much.
| Grade | Density (lb/ft³) | vs carbon |
|---|---|---|
| A36 carbon steel | ~490 | baseline |
| 4140 alloy steel | ~490 | same |
| Spring steel | ~490 | same |
| Tool steel (A2) | ~489 | −0.2% |
| 316 stainless | ~500 | +2.0% |
| 304 stainless | ~501 | +2.2% |
Grade barely moves the weight — stainless is about 2% heavier than carbon steel, and alloy, tool and spring steels are within a percent. Size and profile dominate; density just fine-tunes it.
A piece’s weight comes from four things: the profile and its size give the cross-section, the length turns that into volume, and the grade’s density turns volume into the pounds you rig and lift.
- Length is linear — twice the length is twice the weight, for any profile.
- Size is squared — doubling a bar’s diameter or a square’s side quadruples the weight per foot.
- Tube saves weight — only the wall carries metal, so a tube is far lighter than a solid bar of the same OD.
Everything the calculator works out
One set of inputs gives you the total weight and per-piece weight, in pounds and kilograms, the weight per foot and the cost — plus a comparison across grades and quantities, and a report to save.
The figures behind every piece
Built for anyone cutting, buying or lifting steel
A bar, a tube, a plate, a weldment — the weight decides the freight, the rigging, the price and whether it’s a forklift job. Knowing it before you order or lift saves a surprise at the dock or the crane.
Cutting bar, tube and plate to size for frames and brackets, and needing weight per part for handling and quoting.
- Weight per piece and run total
- Compare profiles and grades
- Save the PDF to the job
Pricing steel by weight and planning freight, where the weight per piece drives both the quote and the shipping.
- Price per pound or per ton
- Total weight for freight
- Compare grades by cost
Planning a lift where the weight sets the sling, the crane capacity and whether it’s a one- or two-pick job.
- Per-piece weight for the pick
- Size slings to the load
- Plan forklift vs crane
7 tips for working out steel weight
The things that throw off a steel estimate or a lift — and the checks that keep the weight accurate and the handling safe.
Steel weight FAQ
The weight, profile and grade questions people ask most when sizing, buying or lifting steel stock.
Weight is cross-section area times length times density. Work out the area of the profile, multiply by the length, then by the steel density — about 490 lb per cubic foot (0.2836 lb per cubic inch) for carbon steel.
The area formula is what changes between shapes: a round bar is π ÷ 4 × diameter², a square bar is the side squared, a sheet is width times thickness, and a tube is the outer ring area. The calculator handles every profile and grade, and gives weight per piece, per foot and in total.
For carbon steel, a round bar weighs about 2.67 pounds per foot for every inch of diameter squared. So a 1-inch bar is about 2.67 lb/ft, a 2-inch bar about 10.7 lb/ft, and a 1/2-inch bar about 0.67 lb/ft.
That comes from the circle area (π ÷ 4 × diameter²) times the density. Weight rises with the square of the diameter, so doubling the diameter quadruples the weight per foot. The calculator gives the exact figure for any diameter and grade.
Carbon steel weighs about 0.2836 pounds per cubic inch, which is 490 lb per cubic foot or roughly 7.85 grams per cubic centimeter. That single figure drives every steel-weight calculation.
Stainless grades are a touch heavier at around 0.29 lb per cubic inch (about 500 lb per cubic foot), while alloy, tool and spring steels sit within a percent of carbon steel. The calculator uses the right density for the grade you pick.
Slightly. Stainless grades like 304 and 316 run about 500 to 501 lb per cubic foot, versus about 490 for carbon steel — roughly 2 percent heavier. On most parts that is a small difference, a few pounds on a typical bar or sheet.
Alloy steels like 4140, plus tool and spring steels, are all within a percent of carbon steel, so grade changes the weight only a little. The by-grade table compares them side by side for your exact size.
A tube’s weight uses the ring area — the outer circle minus the hollow inner circle. Take π ÷ 4 × OD², subtract π ÷ 4 × ID² (inner diameter is the OD minus twice the wall), then multiply by length and density.
Because only the wall carries metal, a tube weighs far less than a solid bar of the same outer diameter. In the calculator, choose Round tube and enter the outer diameter and wall thickness and it works out the ring area for you.
A steel sheet’s weight is its area times thickness times density. A handy shortcut: carbon steel weighs about 40.8 lb per square foot for every inch of thickness, so roughly 10.2 lb per square foot at 1/4 inch.
A full 4 by 8-foot sheet is 32 square feet, so at 1/4 inch it is about 327 lb, and at 1/8 inch about 163 lb. Enter the width, thickness and length in the calculator and it gives the exact weight for any grade.
Mills roll and draw steel to a size tolerance, so a nominal dimension can run slightly over or under, and small differences add up on a long bar or big sheet. Grade, surface finish and whether stock is hot-rolled or cold-finished also shift the real weight a little.
The calculator uses nominal sizes and a standard density, which is accurate for estimating, pricing and planning freight. For a precise shipped weight, confirm against the supplier’s mill certificate.
Multiply pounds by 0.4536 to get kilograms, or divide kilograms by 0.4536 to go back. So a 327-pound plate is about 148 kg, and a 100-pound bar is about 45 kg.
The calculator shows both units at once, so the figure works whether your supplier or drawing uses imperial or metric. It also gives weight per foot and per piece, which are the numbers most used for ordering and rigging.
Estimate Only — Confirm With Your Steel Supplier: This calculator finds weight as cross-section × length × density, using typical densities (carbon steel ≈ 490 lb/ft³ or 0.2836 lb/in³, about 7.85 g/cm³; stainless grades run a little heavier). It assumes solid, uniform stock at nominal size. Mill rolling and drawing tolerances, grade, surface finish and whether stock is hot-rolled or cold-finished shift the real weight, and holes or cutouts reduce it. Use the result to plan material, cost, freight and rigging, not as a certified shipping weight or a structural specification. For reference and estimating only; confirm size, grade, weight and handling limits with your supplier before ordering or lifting.