Stone Weight Calculator
Enter the shape and dimensions of your stone, choose a material, and get the weight instantly in pounds, kilograms, metric tonnes, and US short tons. Works for rectangular blocks and slabs, cylindrical columns or cores, and any material where you already know the density. Supports metric and imperial units side by side.
Formula
Worked example
A granite slab 3 ft x 2 ft x 4 in: convert to metres: 0.9144 m x 0.6096 m x 0.1016 m = 0.05667 m3. Multiply by granite density 2691 kg/m3: 0.05667 x 2691 = 152.5 kg (336 lb, 0.168 short tons).
How stone weight is calculated
The formula is straightforward: weight equals volume multiplied by density, scaled by the number of pieces. For a rectangular block or slab, volume is length times width times thickness. For a cylindrical column or core sample, volume is pi times the square of the radius times the height. Once you have volume in cubic metres, multiply by the material density in kg/m3 to get kilograms, then convert to pounds (divide by 0.453592), US short tons (divide by 907.185), or metric tonnes (divide by 1000). The density is the key variable: granite at 2691 kg/m3 weighs significantly more than crushed stone at 1682 kg/m3 for the same volume, because loose aggregate has roughly 30 to 40 percent void space that solid rock does not.
Material densities and why they matter
Stone density varies with mineralogy, grain size, and how much open pore space the rock contains. Dense, crystalline rocks such as basalt and granite sit at the heavy end (2700 to 2800 kg/m3). Carbonate rocks like limestone and marble cluster around 2500 to 2700 kg/m3 depending on purity and porosity. Sedimentary rocks such as sandstone and travertine are lighter because they retain more pore space, typically 2300 to 2500 kg/m3. Crushed aggregate, which includes air gaps between particles, falls well below solid stone at around 1400 to 1700 kg/m3 in bulk. If you have a material data sheet from your supplier, use the custom density option to enter the exact value and get a more precise result.
Safe lifting limits and equipment selection
A single piece weighing up to 23 kg (50 lb) is generally considered safe for one adult to lift manually according to occupational health guidelines. Between 23 and 100 kg, a two-person lift or a hand-truck and stone-clamp is appropriate. Pieces above 100 kg should be moved with a forklift, telehandler, or crane with a suitable lifting harness or stone tongs. Armour stone and large granite blocks for retaining walls can exceed 2000 kg each and require a crane rated for the full load including the lifting gear. Always confirm rated capacities and add a safety margin of at least 25 percent when specifying equipment.
Delivery truck and trailer payload reference
Knowing the total weight of your stone order helps you select the right vehicle and avoid overloading. A typical flatbed pickup truck (half-ton) carries roughly 500 to 700 kg. A 3/4-ton pickup reaches around 900 kg payload. A single-axle dump truck commonly handles 5 to 7 metric tonnes, and a tandem-axle truck can carry 10 to 14 tonnes. Semi-trailers can carry 20 tonnes or more depending on axle configuration and local road regulations. Overloading a vehicle damages suspension and brakes and can be illegal; always confirm your total order weight and match it to a vehicle with adequate rated capacity.
Standard stone densities
| Material | Density (kg/m³) | Density (lb/ft³) | Typical use |
|---|---|---|---|
| Granite | 2691 | 168 | Countertops, kerbs, monuments |
| Limestone (solid) | 2611 | 163 | Walling, flooring, facade cladding |
| Marble | 2563 | 160 | Flooring, sculptures, cladding |
| Quartzite | 2650 | 165 | Flooring, staircases, outdoor paving |
| Basalt / Armour Stone | 2803 | 175 | Armour rock, sea walls, base course |
| Slate | 2750 | 172 | Roofing, flooring, chalkboards |
| Travertine | 2500 | 156 | Flooring, pools, facades |
| Sandstone | 2323 | 145 | Walling, paving, heritage restoration |
| Crushed Stone / Gravel | 1682 | 105 | Base course, drainage, concrete aggregate |
Engineering average densities used in this calculator. Actual values vary with porosity and moisture content.
Frequently asked questions
How do I calculate the weight of a stone slab?
Multiply the length by the width by the thickness to get the volume, keeping all three measurements in the same unit. Then multiply by the density of the material. For example, a granite slab 1.2 m x 0.6 m x 0.03 m has a volume of 0.0216 m3. At 2691 kg/m3, that slab weighs about 58 kg (128 lb). This calculator does all three steps automatically and shows the working.
What is the density of granite?
Granite has an average density of about 2691 kg/m3 (168 lb/ft3). The range across different granite types is roughly 2600 to 2750 kg/m3 depending on mineralogy. If your supplier provides a specific density on a material data sheet, you can enter it using the custom density option for a more accurate result.
How much does a cubic yard of crushed stone weigh?
Crushed stone and gravel typically weigh 1.4 to 1.7 short tons per cubic yard (about 1270 to 1540 kg/m3) in bulk, because the aggregate includes air gaps between particles. This calculator uses 1682 kg/m3 (105 lb/ft3) as the default for the crushed stone preset, which is a common engineering value. The actual weight depends on particle size, gradation, and moisture content.
How much does limestone weigh per cubic foot?
Solid limestone weighs approximately 163 lb per cubic foot (2611 kg/m3). This applies to a continuous block or slab. Crushed limestone used as aggregate or road base weighs less per cubic foot because of voids between pieces, typically around 90 to 100 lb/ft3.
What weight is too heavy to lift by hand?
Occupational health guidelines in most countries set 23 kg (50 lb) as the upper limit for a solo manual lift under ideal conditions. Awkward shapes, slippery surfaces, or lifting from floor level all reduce this limit. For anything heavier, use a two-person team, a mechanical hand-truck, a pallet jack, or a forklift. This calculator flags the lifting category for each piece weight.
How do I estimate weight for irregularly shaped stones?
Use the "I know the volume" option and enter the volume directly. You can measure the volume of an irregular stone by water displacement: submerge it in a container of water and measure how much water it displaces. Record the displaced volume in litres (1 litre = 0.001 m3), enter it in the calculator, select your material, and you will get the weight. Alternatively, weigh a similar-sized regular block of known material and use the ratio.