Concrete Calculator
Calculate the amount of concrete needed for your project. Enter dimensions to get cubic yards and number of bags required.
Cubic Yards
0
80-lb Bags
0
60-lb Bags
0
Includes 10% waste factor
How to calculate concrete needed.
Concrete is measured in cubic yards. To calculate: multiply length × width × depth (all in feet) to get cubic feet, then divide by 27 to convert to cubic yards. Always add 10% extra for waste, spillage, and uneven surfaces.
For small projects, pre-mixed bags are practical. An 80-lb bag yields about 0.6 cubic feet of concrete. For anything over 1 cubic yard, ordering ready-mix from a truck is more cost-effective.
Frequently asked questions.
How thick should a concrete slab be?
Standard sidewalks and patios need 4 inches. Driveways should be 4–6 inches. Garage floors and areas with heavy loads need at least 6 inches. Always check local building codes.
Should I order extra concrete?
Yes, always order 10% more than calculated. Concrete is difficult to match later, and running short mid-pour creates weak joints. It's better to have a little extra than not enough.