Quikrete Sonotube Calculator

Calculate concrete volume, required 80‑lb bags and cubic yards instantly for free.

  • Free
  • No sign-up
  • Instant results

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How to use it

  1. Enter the tube diameter in inches.
  2. Enter the depth in feet.
  3. Specify how many tubes you need.
  4. Read the cubic yards, cubic feet, and bag count.

What it does – The Quikrete Sonotube Calculator turns the dimensions of your concrete column into three practical numbers: total cubic feet, cubic yards, and how many 80‑lb bags you’ll need. Knowing the exact volume prevents over‑ordering, saves money, and keeps the job on schedule. The calculator uses the standard conversion that one 80‑lb bag yields about 0.6 ft³, and 27 ft³ = 1 yd³, so the results are directly tied to the material you’ll purchase. How to read it – Cubic feet shows the raw volume of the tube, cubic yards is the industry‑standard unit for delivery, and 80‑lb bags tells you the exact bag count before rounding. Use the numbers to place an accurate order and avoid costly waste. The tool also helps you verify that the tube fits within local code limits and that the concrete strength matches the intended load. When you change the diameter or depth, the calculator updates instantly, so you can experiment with different sizes before buying.

Pro tips

  • Add about 10% extra for waste and spillage.
  • Always round up the bag total to the next whole bag.
  • Order a few extra bags if delivery trucks have minimum loads.
  • Confirm tube length fits the site clearance before ordering.

Real-life examples

  • A homeowner pouring a 10‑in Sonotube footing for a new deck post.
  • A contractor estimating concrete for multiple 8‑ft deep footings on a commercial site.
  • A DIY gardener installing a concrete pier for a raised garden bed.

Case study

Mike needed a 12‑in diameter, 8‑ft deep footing for a new fence post. Using the calculator, he saw he required 1.78 yd³, which translates to 10 bags. He ordered 10 bags, saved $30 by avoiding a 12‑bag order, and finished on schedule.

Frequently asked questions

How many 80‑lb bags are needed for a 6‑in diameter, 4‑ft deep Sonotube?
Enter the dimensions; the calculator will convert the volume to cubic feet, then divide by 0.6 ft³ per bag and round up.
Do I need to add waste when ordering concrete?
Yes, add about 10% to the calculated bag count to cover spillage and minor over‑fill.
What unit is used for delivery?
Concrete is typically delivered in cubic yards; the calculator provides this conversion automatically.
Can I calculate multiple tubes at once?
Enter the quantity of identical tubes; the results will be multiplied accordingly.
Is the calculator accurate for other brands?
The 0.6 ft³ per 80‑lb bag is standard for most mixes, so results are reliable across brands.