Concrete Calculator

What are you pouring? (count)

Choose Slab for a flat rectangular pour, Footing for a rectangular trench, or Round column or post hole for a cylinder. Your choice decides which fields below apply.

Slab length

Enter the slab's length in feet, from 0.1 to 1000 ft.

Slab width

Enter the slab's width in feet, from 0.1 to 1000 ft.

Slab thickness

Enter the slab's thickness in inches, from 2 to 48 in.

Bag size (lb)

Pick the bag size you plan to buy. It fills in a typical yield for that size below, which you can still edit.

Yield per bag

Enter the volume one bag yields, in cubic feet, from 0.05 to 3 ft³. Picking a bag size above fills in a starting value.

ft³

Waste allowance

Enter a percent to add on top of the raw volume for spillage or an uneven sub-base, from 0 to 50%.

Results

Concrete volume for bag counting is 33.33 ft³. Concrete volume for ready-mix ordering is 1.23 yd³. Bags needed is 56. Placed weight is 4667 lb.

Concrete volume for bag counting
Concrete volume for ready-mix ordering
Bags needed
Placed weight