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Project Type & DimensionsAffiliate Disclosure: This calculator is free to use. Some product links are affiliate links. Product links and pricing are for the US market.
How This Calculator Works
- Slabs: Volume = Length x Width x Thickness. Converted to cubic yards (1 cubic yard = 27 cubic feet).
- Post holes: Volume = pi x radius^2 x depth per hole, times number of holes.
- Bag yields: An 80 lb bag yields 0.6 cubic feet. A 60 lb bag yields 0.45 cubic feet. A 50 lb fast-set bag yields 0.375 cubic feet.
- Ready-mix: Order from a concrete truck when you need 1+ cubic yards. Bags are impractical above 1 yard (45 bags of 80 lb = over 3,600 lbs of mixing). Most ready-mix companies have a 1-yard minimum with a short-load fee for under 5 yards.