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Prices updated January 2026

Concrete Column & Tube Calculator

Cubic yards and bags for round columns, piers and sonotubes — diameter, height and count.

Concrete column calculator

Shape

Waste factor

Concrete needed (waste in)

5.43 yd³

146.7 ft³ · 4.15

Bags (rounded up)

245

80 lb

326

60 lb

392

50 lb

489

40 lb

Ready-mix (delivered)
$739 – $1,207
Bagged (80 lb)
$1,348 – $2,205
Installed (slab)
$2,200 – $4,800
How much will this cost? →
Concrete 5.43 yd³

Sizing round columns & sonotubes

A round column is a cylinder: π × radius² × height. Enter the diameter in inches, the height in feet, and how many identical columns you're pouring — the calculator totals them and rounds bags up. For deck and fence footings, see the post-hole calculator.

Prices updated January 2026 National US averages · reviewed quarterly

Volumes use standard bag yields and a 10% waste allowance; costs are national US averages that vary by region, mix and finish. See our methodology for exactly how each figure is worked out, or check the reference sources:

Concrete calculators

Frequently asked questions

How much concrete for a round column?
Volume is π × radius² × height. A 12" diameter column 10 ft tall holds about 0.29 cubic yards — roughly 13 × 80 lb bags. Enter your size and count above.
What is a sonotube?
A cardboard forming tube for casting round concrete columns and piers. Its diameter is the column diameter you enter here.
How many bags for a sonotube?
It depends on diameter and height. The calculator rounds bags up for every size once you enter the tube dimensions.