Calculate how much concrete (in cubic meters and tons) you need for a slab, footing, or foundation.
📂 Concrete & Masonry MaterialsFill in the fields on the left with your project's measurements, then press the button to see your result instantly. No sign-up required, and no data is sent anywhere — everything is calculated right in your browser.
This tool calculates the amount of concrete needed for a slab, foundation, or footing in cubic meters, based on the area's dimensions (length and width) and the required pour thickness in centimeters, converting these into a straightforward volume calculation. It can also calculate several identical sections at once, such as multiple columns or footings of the same size, by multiplying the single-unit volume by the quantity needed, which speeds up estimation for repetitive structural elements common in residential and commercial construction. The tool automatically adds a standard 5% wastage allowance to account for natural losses during pouring, spillage, and mixing inconsistencies, and also shows the estimated weight in metric tons using the standard concrete density of approximately 2,400 kg per cubic meter, which is useful for coordinating delivery logistics with ready-mix suppliers. This result represents the volume of ready-mix concrete needed, or the target volume before manual mixing; to convert it into the actual amounts of cement, sand, and gravel required at a specific mix ratio for a self-mixed pour, use the linked Cement Calculator, since that calculation requires the separate dry-volume adjustment covered there.
Ordering the right amount of concrete for a pour is one of those calculations where being wrong in either direction creates real problems: ordering too little means a visible cold joint where an incomplete pour has to be topped off later, weakening the structural continuity of the slab, while ordering significantly too much means paying for wasted ready-mix concrete that has to be disposed of, since it can't be returned once mixed.
The core calculation is straightforward geometry — length times width times thickness gives volume — but the practical challenge is usually unit consistency and remembering to convert pour thickness, which is almost always specified or thought about in centimeters or inches, into the same length unit as the area dimensions before multiplying, since mixing units is one of the most common sources of estimation errors on a job site.
For projects with multiple identical structural elements — a row of column footings, several equally-sized piers, or a series of matching slab sections — calculating one unit's volume and multiplying by the total count is both faster and less error-prone than calculating each section separately, provided the elements really are identical in dimension, which is worth double-checking against the actual structural drawings before assuming uniformity.
The standard 5% wastage allowance added to concrete orders reflects real-world pour losses: some concrete inevitably spills during placement, some remains in the truck's drum or pump lines after delivery, and formwork isn't always perfectly sealed, allowing minor leakage during the pour. Experienced contractors build this margin into their orders as standard practice rather than an optional buffer.
Knowing the estimated weight in tons, calculated from the volume using concrete's standard density, matters for a different practical reason: ready-mix trucks have maximum load capacities, and larger pours may need to be split across multiple truck deliveries or coordinated with pump truck scheduling — information a contractor needs well before pour day, not as an afterthought once the truck arrives and can't fit the entire order.
Yes, a standard 5% wastage allowance is automatically added to the base volume to account for spillage and minor variations in thickness.
Yes, as long as you can express the shape as length × width × thickness (or treat a column as a small rectangular section), this calculator works for footings, slabs, and columns.
Use the Cement Calculator (linked below) with the total volume from this tool to get bags, sand, and aggregate quantities for your specific mix ratio.