Load Weight Estimator
Pick a shape, enter the dimensions and choose a material to get the weight in pounds and short tons. Densities come from published federal sources and are shown on the page. This is an estimate from geometry: for a lift, the weight still has to be confirmed from the nameplate, the shipping papers or a scale.
Estimated weight
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Results are estimates for planning purposes and do not replace a competent person's evaluation or an engineer's design. Follow the OSHA standards that apply to your work and your employer's written program.
Densities used, and where each one comes from
| Material | lb/ft³ | kg/m³ | Source |
|---|---|---|---|
| Structural steel | 490 | 7,849 | FHWA NHI-04-041, citing AASHTO LRFD Table 3.5.1-1 |
| Reinforced concrete | 150 | 2,403 | FHWA NHI-04-041, citing AASHTO LRFD Table 3.5.1-1 |
| Fresh water | 62.4 | 1,000 | FHWA NHI-04-041 |
| Compacted soil | 120 | 1,922 | FHWA NHI-04-041, citing AASHTO LRFD Table 3.5.1-1 |
| Aluminium (pure) | 168.5 | 2,699 | NIST, elemental density 2.699 g/cm³ |
| Copper (pure) | 559.4 | 8,960 | NIST, elemental density 8.960 g/cm³ |
| Lead (pure) | 708.6 | 11,350 | NIST, elemental density 11.35 g/cm³ |
| Titanium (pure) | 283.4 | 4,540 | NIST, elemental density 4.540 g/cm³ |
The NIST values are for the pure element; commercial alloys sit a few percent either side. Structural steel is 490 lb/ft³ by long-standing convention rather than by measurement of your particular grade. Anywhere a few percent matters, use the mill certificate, the mix design or the manufacturer's data — and put it in the custom density field.
An estimate is not a load weight
Geometry and a published density give you a number to sanity-check against. They do not tell you what is inside the vessel, what is bolted to the underside of the skid, whether the concrete is still green, or how much water the load has soaked up in the yard. Before the pick:
- Get the weight from the nameplate, the shipping documents, the drawing or a scale. 29 CFR 1926.1417(o)(3) requires the crane operator to be given the weight of the load before it is lifted.
- Add the rigging — slings, shackles, spreader bars, below-the-hook devices — to what the hook actually picks up.
- Round up, never down. The failure mode of an underestimated load is not a slow one.
- Then work out the tension in each leg with the sling tension calculator and compare it with the rated capacity on the sling's tag.
How it's calculated
- Rectangular solid
V = length × width × thickness- Cylinder
V = π × (diameter / 2)² × length- Round pipe or tube
V = π × [(OD / 2)² − (OD / 2 − wall)²] × length- Rectangular tube
V = [width × height − (width − 2 × wall) × (height − 2 × wall)] × length- Sphere
V = (4 / 3) × π × (diameter / 2)³- Weight
weight = V (ft³) × density (lb/ft³) × number of piecesA short ton is 2,000 lb. Densities are published values for the material, not for your particular alloy, mix or moisture content.- Density conversion
1 g/cm³ = 62.427960576 lb/ft³Used to convert the NIST elemental densities into pounds per cubic foot.
Frequently asked questions
No, and this page is not trying to pretend otherwise. It gives you the order of magnitude and a sanity check on the number somebody handed you. For the lift itself, use the nameplate, the shipping documents, a load cell or a scale; 29 CFR 1926.1417(o)(3)(i) requires the weight of the load to be determined from a source or a calculation method recognized by the industry, and provided to the crane operator before the lift when the operator asks for it.
Structural steel (490 lb/ft³), reinforced concrete (150 lb/ft³), fresh water (62.4 lb/ft³) and compacted soil (120 lb/ft³) are the values used in FHWA's public LRFD design example, taken from AASHTO's dead-load table. Aluminium, copper, lead and titanium come from NIST's tabulated elemental densities, converted at 62.427960576 lb/ft³ per g/cm³.
Because there is no single number. Wood density depends on the species and on the moisture content, and the same nominal 2×10 can differ by half again between a dry softwood and a green hardwood. The USDA Wood Handbook is the reference; look up your species and moisture content and put the figure in the custom density field.
Close, not exact. The NIST figures are for the pure element, and structural steel is 490 lb/ft³ by convention. Real alloys sit a few percent either side — 6061 aluminium and cast iron are both noticeably different from the generic figure. For anything where a few percent matters, use the mill certificate or the manufacturer's data.
No. Slings, shackles, spreader bars, below-the-hook devices and anything left inside the load all add to what the hook picks up. Add them separately — the sling tension calculator has a field for the weight of the rigging.
Break it into pieces you can describe — a skid as a rectangular solid, its legs as tubes — and add the results, or work out the volume yourself and use the “Known volume” shape. When in doubt, round up: an underestimated load is the one that hurts people.
2,000 pounds. It is the ton used for loads and crane charts in the United States, and it is not the metric tonne (2,204.6 lb) or the long ton (2,240 lb). This calculator reports short tons in imperial mode and metric tonnes in metric mode.
No, and that catches people out. Pick “Round pipe or tube” for the steel, then run the calculator again with the inside diameter as a solid cylinder of water or whatever is in it, and add the two. A pipe with a 12 in inside diameter, 20 ft long, holds 15.7 ft³ — about 118 gallons, roughly 980 lb of water on top of the steel.
Sources & references
- FHWA NHI-04-041 — LRFD Design Example for Steel Girder Superstructure Bridge: steel 0.490 kcf, concrete 0.150 kcf, water 62.4 pcf, soil 0.120 kcf (citing AASHTO LRFD Table 3.5.1-1)
- NIST — X-Ray Mass Attenuation Coefficients, Table 1: elemental densities in g/cm³ (aluminium 2.699, copper 8.960, lead 11.35, titanium 4.540)
- USDA Forest Products Laboratory — Wood Handbook: Wood as an Engineering Material (FPL-GTR-282, 2021): wood density varies with species and moisture content, which is why no single lumber figure is offered here
- 29 CFR 1926.251 — Rigging equipment for material handling: slings may not be loaded in excess of their rated capacities
- 29 CFR 1926.1417(o)(3) — the weight of the load must be determined from a source or calculation method recognized by the industry, and provided to the crane operator before the lift when the operator requests it
Content checked against these sources — last reviewed August 27, 2026.