Concrete calculator for slabs, footings and post holes
Pick the job below to get cubic yards and bag counts for a concrete slab, a footing, a fence post hole or a Sonotube column. There are also calculators for mulch and paver base. Every bag yield and every rule of thumb on this site comes from a manufacturer data sheet or a public reference, linked on the page with the date we last checked it.
Concrete
Concrete SlabPatios, pads and shed floors: cubic yards and bag counts.
Fence Post HoleConcrete per hole with the post subtracted, then for the whole fence line.
Sonotube / Round ColumnRound form tubes for deck piers and columns.
FootingContinuous strip footings and square pads.
Concrete Block WallBlocks, mortar bags and core-fill grout for an 8 x 16 block wall.
Landscaping
Hardscape
Why trust the numbers
If a calculator on this site uses a number that isn't pure geometry — how much a bag yields, how thick a layer should be — the page shows where that number comes from, links to the source, and says when we checked it. The full list is on the sources page. Where we can't find a source we can cite, we leave the choice to you instead of guessing.