Concrete Slab & Footing Volume Calculator

Understanding Concrete Volume Calculations

Concrete volume is measured in cubic yards, the standard unit used by ready-mix suppliers. For small projects, concrete is purchased as pre-mixed bags (60lb or 80lb). Accurately calculating volume prevents costly over-ordering or mid-project shortages.

The Core Formula

When to Order Ready-Mix vs. Bags

For projects over 0.5 cubic yards, ordering ready-mix concrete from a truck is more economical than mixing bags. For very small projects like fence posts or steps, premixed bags (Quikrete/Sakrete) are most practical. Always add at least 10% extra to account for waste, settling, and form overflow.