Marble Slab Calculator
Calculate the weight and dimensions of marble slabs for countertops, flooring, or other projects.
Quick Answer
Marble weighs about 170 lb per cubic foot — roughly 14 lb per square foot for each inch of thickness. A 3 cm (1.18 inch) slab weighs about 16–17 lb per square foot, so multiply the slab area by that figure for total weight.
Marble Slab Calculator Guide
Marble is one of the heaviest stones you'll work with, so knowing a slab's weight before you order or move it is essential for transport, support, and safe handling. Our marble slab calculator estimates the weight of a slab from its length, width, and thickness, using marble's typical density of around 170 lbs per cubic foot.
Whether you're planning a countertop, a tabletop, flooring, or a vanity, an accurate weight tells you how many people (or what equipment) you'll need to carry it, and whether your cabinets or base can support it. For other stone types, compare with our stone slab weight calculator.
Finish and Handle Marble the Safe Way
Marble is soft enough to scratch and heavy enough to hurt you, so two things make any DIY marble job safer and cleaner. Diamond polishing pads let you smooth a cut edge or restore a dull surface to a finished shine by working up through the grits — the difference between a raw saw cut and a professional edge. And because cutting or grinding marble throws fine silica and stone dust, a proper respirator is non-negotiable for protecting your lungs.
Diamond Polishing Pads
Work up through the grits to turn a raw cut edge into a smooth, finished shine.
Check Price on AmazonDust Respirator
Cutting and polishing marble releases fine dust — protect your lungs first.
Check Price on AmazonThe product links above are affiliate links — at no extra cost to you.
Frequently Asked Questions
How much does a marble slab weigh?
Marble weighs roughly 170 lbs per cubic foot. A standard 3cm (1.25 inch) thick slab weighs about 18-19 lbs per square foot, so a 6 ft x 3 ft countertop slab weighs around 330-350 lbs. A 2cm slab is about 12-13 lbs per square foot.
How many people do I need to move a marble slab?
As a rule of thumb, plan one person per 80-100 lbs, and always carry slabs on edge (vertically) rather than flat to prevent cracking. A typical countertop slab needs at least 2-3 people plus slab-carrying straps or clamps.
Is marble too heavy for standard cabinets?
Standard, well-built cabinets can support marble countertops, but the cabinet boxes must be level and properly secured. For long spans or thin cabinet tops, add plywood support or extra bracing to distribute the weight safely.
How is marble weight different from granite or quartz?
Marble (~170 lb/ft³) is slightly lighter than granite (~170-180 lb/ft³) and similar to quartz. The practical difference is small; the bigger factor in total weight is slab thickness (2cm vs 3cm) and overall dimensions.