Concrete Column Calculator
Larger round forms — porch columns, pier foundations, drilled piers. Same geometry as a Sonotube; the defaults are a 16″ column at 8 ft. For square columns use the slab calculator with the column footprint as length × width.
Order 2.00 yd³ ready-mix — plants ticket in ¼-yd³ and most charge a short-load fee under ~5 yd³.
- Net volume (44.7 ft³)
- 1.65 yd³
- Waste 10%
- + 0.17 yd³
- Ready-mix ticket
- 2.00 yd³
- Approx. weight
- 6,702 lb
- 80 lb bags
- 82
- 60 lb bags
- 110
- 40 lb bags
- 164
- Materials + delivery$5.50–$8 / bag · Sep 2026
- $451 – $656
- Installed (with labor)typ. $1,261
- $906 – $1,839
Quantities follow the ticket. Links may earn us a commission at no cost to you; they never change a number.
How to calculate sonotube by hand
Cubic feet per tube = π × (Diameter (in) ÷ 24)² × Height (ft) · 80 lb bags = ft³ ÷ 0.60
Worked example
- Radius: 12 in ÷ 2 = 6 in = 0.5 ft.
- Per tube: π × 0.5² × 4 ft = 3.14 ft³.
- Six tubes: 3.14 × 6 = 18.8 ft³; with 10% waste 20.7 ft³ = 0.77 yd³.
- Bags: 20.7 ÷ 0.60 = 35 × 80 lb bags (about 6 per tube) — under 1 yd³, so bags.
- 8″ tube
- 0.35 ft³ per ft · 0.6 × 80 lb bags per ft
- 10″ tube
- 0.55 ft³ per ft · 0.9 bags per ft
- 12″ tube
- 0.79 ft³ per ft · 1.3 bags per ft
- 16″ tube
- 1.40 ft³ per ft · 2.3 bags per ft
Questions crews ask
How much concrete is in a 16-inch column?
1.40 ft³ per foot of height, so an 8 ft column is 11.2 ft³ = 0.41 yd³ each. Four of them are 1.66 yd³ — order 1.75 yards with waste; that is a short load, not a bag job.
How do I calculate concrete for a square column?
Width × depth × height, all in feet. A 12 × 12″ column 8 ft tall is 1 × 1 × 8 = 8 ft³ = 0.30 yd³. The slab calculator does this if you enter the footprint as length and width and the height as thickness in inches.
What psi concrete for columns?
3,000 psi for porch and pier columns; 4,000 psi or per the engineer for structural columns, which will also have a specified rebar cage. Vibrate or rod round forms to eliminate voids against the form.