How to use it
- Enter the tube diameter in inches.
- Enter the depth in feet.
- Set the number of tubes you need.
- Read cubic feet, cubic yards and bag count.
What it does – Enter the tube’s inside diameter (inches), its depth (feet) and how many tubes you’re pouring. The tool instantly returns the total volume in cubic feet, the equivalent in cubic yards, and the number of standard 80‑lb bags required.
Why it matters – Ordering the right amount prevents costly over‑order and avoids project delays from running short. Concrete volume directly translates to material cost and crew time.
How to read the results – Cubic feet shows the raw space, cubic yards is the industry‑standard unit for delivery, and the bag count is rounded up to the nearest whole bag because you can’t purchase a fraction. You can also multiply the single‑tube result by the quantity field to plan larger jobs in seconds. The calculator accounts for the exact 0.6 ft³ per 80‑lb bag, so the bag total is always realistic. For a 12‑in tube 6 ft deep, the calculator shows 4.7 ft³, 0.17 yd³ and 8 bags.
Pro tips
- Add 5‑10% extra for spillage and settling.
- Always round up to the next whole bag—you can’t buy a partial bag.
- Order bags in multiples of 5 for better delivery pricing.
- Double‑check the diameter; interior measurement matters more than exterior.
Real-life examples
- A DIY homeowner building a concrete footing for a shed.
- A contractor estimating material for multiple fence post footings.
- A landscaper filling decorative concrete planters on a job site.
Case study
Mike needed concrete for three 12‑in sonotubes, each 6 ft deep. Using the calculator he saw he required 4.7 ft³ total, 0.17 yd³ and 8 bags, so he ordered exactly eight 80‑lb bags and avoided a costly over‑order.