Stone weight matters for anything from picking a countertop dolly to ordering the right size truck for a delivery of gravel. This calculator handles the three common ways stone gets measured — a solid slab, a solid block, or a loose volume of fill — and applies the correct density for each so the number you get matches how the stone is actually sold and handled.
How the Stone Weight Calculator works
The math is simple: weight equals volume times density. The calculator figures volume from the dimensions you enter for your chosen shape — length × width × thickness for a slab, length × width × height for a block, or a direct volume entry for loose fill. It then multiplies that volume by a density value drawn from standard construction and geology reference tables.
For solid stone (slab or block), the calculator uses the parent rock's solid density — no gaps, no air pockets, just continuous stone. Granite, marble, and basalt run heavier (168-180 lb/ft³); sandstone and limestone run lighter (145-155 lb/ft³). For loose stone (gravel, crushed stone, rip-rap), it switches to a lower effective bulk density of 100 lb/ft³, because a pile of loose pieces always has empty space between them that a solid slab does not.
Inputs and what they mean
Slab dimensions are entered in feet for length and width (typical countertop/paver scale) and inches for thickness, since slab thickness is almost always specified in fractions of an inch (1.25 in is a common countertop thickness). Block dimensions are entered entirely in inches, matching how concrete and stone masonry blocks are typically spec'd. Loose volume skips linear dimensions entirely and accepts a direct volume in cubic feet, cubic yards, or cubic meters — cubic yards is the unit most gravel and landscape suppliers quote and bill by.
The stone type picker (Granite, Limestone, Marble, Sandstone, Basalt, Slate) only appears for Slab and Block, since loose fill always uses the gravel bulk density regardless of what rock it was crushed from — the packing factor dominates the calculation more than the parent rock's exact density.
Limits and edge cases
These are standard reference densities, not a substitute for a supplier's spec sheet — actual quarry stone can vary a few percent depending on mineral composition and moisture content. Loose gravel density in particular can range from about 90 to 110 lb/ft³ depending on how tightly it has settled or been compacted; 100 lb/ft³ is a reasonable mid-range estimate for planning and quoting, but a supplier's exact bulk density figure should be used for load-limit or structural calculations. For heavy loads (multi-ton slabs, full truckloads of gravel), always confirm the final number against a certified scale weight before committing to a shipping method, crane rating, or vehicle payload limit.