Project Volume Calculator
Enter measurements to get an instant estimate. No sign-up needed.
Geometric volume plus any chosen allowance
Illustrative normal-weight cured concrete density. Ready-mix order volume is not converted from this density. Allowances and costs are estimates; verify supplier units and field conditions.
How to calculate concrete yardage
Multiply length in feet by width in feet by thickness in inches, then divide by 324. For non-rectangular slabs, break the footprint into measurable shapes and calculate each volume separately.
The result is the geometric quantity. Actual concrete orders can require extra volume for uneven subgrade, edge thickening, grade variation or construction waste.
Concrete slabs versus footings
Slabs are often estimated from surface area and thickness, while footings require their own width, depth and total length. Circular piers and columns require a cylinder formula instead of a rectangle formula. Do not apply a slab formula to every concrete shape.
Ready-mix and bagged concrete
Ready-mix concrete is typically quoted by cubic yard. Bagged concrete is estimated using the yield printed on the exact product packaging, not simply its weight. A bag's concrete yield varies by bag size and product.
Before ordering concrete
Confirm dimensions, elevations, thickened edges and any separately measured footings. The calculator does not verify structural adequacy, code compliance or mix specifications. For structural work, follow the project's plans and professional guidance.
Frequently Asked Questions
How many yards of concrete for a 10 × 10 slab at 4 inches?
Approximately 1.23 cubic yards of geometric concrete volume.
Should I round a concrete order up?
Concrete is ordered according to supplier increments and actual conditions. Confirm quantities and any allowance with the ready-mix supplier or contractor.
Related Calculators and Guides
Continue with a material-specific estimate, convert units, or review the calculation behind your result.