How to use it
- Enter the tube diameter in inches.
- Enter the tube height in feet.
- Enter the number of tubes you need.
- Read the cubic yards, 80‑lb bag count, and cubic‑feet totals.
This calculator tells you exactly how much concrete is required for any number of sonotubes. You input the tube's inside diameter, its depth, and how many you plan to pour. The tool instantly converts those dimensions into three useful units: total cubic yards (the standard ordering unit for deliveries), the number of 80‑lb bags (useful for small‑scale jobs), and total cubic feet (helpful for comparing to material specs). Knowing these numbers prevents over‑ordering, saves money, and keeps your project on schedule. The results are based on the industry‑standard that one 80‑lb bag yields about 0.6 cubic feet, so you can trust the output for budgeting and ordering.
Pro tips
- Add 5‑10% extra for spillage and settling.
- Round up the bag count; you can’t buy a fraction of a bag.
- Order concrete a day before you pour to avoid delays.
- Double‑check the diameter measurement; interior size matters more than exterior.
Real-life examples
- A homeowner building a 4‑ft fence post needs to know concrete bags for three 12‑in sonotubes.
- A contractor estimating material for a row of 8‑ft driveway columns wants total cubic yards for a single delivery.
- A landscaper planning a series of garden pillars wants quick bag counts to price the job.
Case study
Mike was unsure how many 80‑lb bags to buy for five 10‑in sonotubes. Using the calculator, he saw he needed 2.4 cubic yards, which translated to 12 bags. He ordered exactly that amount, avoided a costly over‑order, and completed his patio on schedule.