Concrete Tube Calculator

What this concrete tube calculator is estimating

Tube and post-hole pours are usually estimated as cylinders. Once the diameter and the poured depth are known, the concrete volume of one hole or form tube can be solved cleanly and then scaled by the number of matching pours in the batch.

That makes this page useful for deck piers, fence-post footings, cylindrical tube forms, and similar round pours where the geometry stays constant from top to bottom. The tool gives you both a per-tube volume and a total order figure so it is easier to compare bagged concrete with ready-mix.

Core tube-volume formulas

The calculation converts the entered diameter and depth into a common unit, solves the cylinder volume for one tube, multiplies by the number of tubes, and then applies the waste allowance. The result is then converted into cubic yards or cubic metres and into indicative bag counts for planning.

How to use the tube concrete estimate

Use the total order volume when speaking to suppliers and use the per-tube volume to sense-check the size of each pier or post hole. The bag counts are useful for a handful of small pours, while the ready-mix cue becomes more useful once the total batch grows into a larger order.

For example, six tube pours that are 12 inches in diameter and 4 feet deep need about 0.26 cubic yards of concrete after a 10% waste allowance. That is still manageable as a bagged-mix job in many settings, but the total can rise quickly once the diameter, depth, or count increases.

What this result does not cover

This tool estimates simple cylindrical pours only. It does not include belled or flared footings, gravel-base deductions, reinforcement cages, embedded anchors, or any voids that reduce the true concrete volume. It also assumes the diameter and depth stay constant across the full poured length.

Use it as a planning and ordering aid, then confirm the final pier or footing detail from the drawings, tube specification, and supplier yield information before you place the order.