Calculate how much concrete you need for slabs, columns, footings, stairs, and curbs. Get cubic yards, bags needed, and cost estimates.
Cubic Yards
1.23
Ready-mix order
Cubic Feet
33.3
40 lb Bags
112
0.30 cu ft each
60 lb Bags
75
0.45 cu ft each
80 lb Bags
56
0.60 cu ft each
For projects over 1 cubic yard (like yours!), consider ordering ready-mix concrete for better results and cost savings.
Slab Volume:
V = Length × Width × Depth
Conversion:
33.3 cu ft ÷ 27 = 1.23 cubic yards
To calculate concrete needed: multiply Length x Width x Depth (in feet) to get cubic feet, then divide by 27 to convert to cubic yards. For a 10x10 ft slab that is 4 inches deep: 10 x 10 x 0.33 = 33 cubic feet / 27 = 1.22 cubic yards. Always order 5-10% extra for waste. An 80 lb bag covers 0.6 cubic feet. Ready-mix is more economical for projects over 1 cubic yard.
Calculate volume by multiplying length × width × depth. For a 10×10 ft slab that's 4 inches deep: 10 × 10 × 0.33 = 33 cubic feet = 1.22 cubic yards. Always order 5-10% extra for waste and spillage.
An 80 lb bag yields about 0.6 cubic feet. A 60 lb bag yields about 0.45 cubic feet. A 40 lb bag yields about 0.3 cubic feet. For small projects, bags work well. For anything over 1 cubic yard, consider ready-mix delivery.
Residential driveways should be 4-6 inches thick. Light traffic areas: 4 inches. Heavy vehicles or frequent use: 5-6 inches. Commercial driveways: 6-8 inches. Always use proper base preparation and reinforcement.
Ready-mix concrete costs $100-150 per cubic yard plus delivery ($50-150). Bagged concrete: $4-6 per 80 lb bag. For large projects, ready-mix is more economical. Colored or specialty concrete costs 20-50% more.
Use bagged concrete for small projects under 0.5 cubic yards (like fence posts, small repairs). Use ready-mix for larger projects (driveways, patios, foundations). Ready-mix is more consistent, saves labor, and is cheaper for volume.
Cubic Yards
1.23
Ready-mix order
Cubic Feet
33.3