Concrete Calculator

Start with project dimensions for a ready-mix or bag estimate. Switch to Bags on Hand when you already own bags and want to know how much area they can cover.

Calculation mode

Choose dimensions-to-volume for a project estimate, or bags-on-hand to work backward from an existing bag inventory.

Primary output 1.36 cu yd
Imperial uses feet and inches; metric uses meters and centimeters for thickness/diameters.
Length in feet or meters.
Slab width in feet/meters; strip-footing width in inches/centimeters.
Slab thickness or footing depth. Use inches in imperial mode or centimeters in metric mode.
Used for bag counts, bag-cost mode, and bags-on-hand coverage.
How many premix bags you already have.
Thickness for bags-on-hand coverage, in inches.
Advanced options
Cost — Weight 5,000 lb Warnings —
Optional named project starting point. Preset buttons above can fill the same values faster.
Pick the geometry that matches the pour.
Round-column or post-hole diameter in inches or centimeters.
Column height, post-hole depth, or tube length in feet/meters.
Tube outer diameter in inches or centimeters.
Tube inner diameter; must be smaller than the outer diameter.
Number of identical slabs, columns, holes, or footing runs.
Extra concrete added before order quantity and bag count. 10% is a common residential starting point.
Choose whether optional cost uses cubic yards of ready-mix or rounded-up premix bags.
Optional ready-mix material price for cost estimates.
Optional bag price for cost estimates.
Normal-weight concrete is commonly estimated around 150 lb per cubic foot.
Answer 1.36 cu yd
Concrete volume 1.23 cu yd
Order volume with overage 1.36 cu yd
Selected bag count 62 × 80 lb bags
Estimated material cost —
Show calculation details
Cubic feet 33.33 cu ft
Cubic meters 0.94 m³
40 lb bags 123
60 lb bags 82
80 lb bags 62
Estimated weight 5,000 lb
Notes —