Concrete Calculator
Cubic yards of concrete for slabs, footings, posts, and stairs.
Concrete needed
1.36
cubic yards
Cubic feet
36.7
60 lb bags
82
80 lb bags
62
A 60 lb bag yields about 0.45 cubic feet, an 80 lb bag about 0.6. Pre-mixed concrete is sold by the cubic yard. Round up and order 5 to 10 percent extra for spills and uneven subgrade.
About
Pick a shape, enter dimensions, and see how much concrete to order in cubic yards, bag count for both 60 and 80 pound bags, and total cubic feet. Bulk concrete sells by the yard. For posts and small jobs, bags are easier.
How to use
- Pick the shape (slab, footing, round column, or stairs).
- Enter the dimensions.
- See cubic yards and bag count.
FAQ
60 lb or 80 lb bags?+
80 lb bags are cheaper per cubic foot but heavier to lift. For under 10 cubic feet, bags work. Above that, order ready-mix from a truck.
How much waste should I add?+
5 to 10 percent for slabs and uneven subgrade, more if you have to cut around forms or steel.