Sonotube Concrete Calculator

This sonotube concrete calculator (tube form calculator) gives exact cylinder volumes for cardboard form tubes — deck piers, post bases and columns. Enter diameter, height and how many tubes you're filling.

in
in
5%
$ per yd³

Come usare questa calcolatrice

  1. Inserisci le tue dimensioni — piedi per le lunghezze, pollici per lo spessore.
  2. Regola le opzioni — percentuale di sfrido, dimensione del sacco e il prezzo locale del calcestruzzo.
  3. Leggi i risultati — volume, sacchi, peso e costo si aggiornano in tempo reale mentre digiti.

La formula

Tube volume = π × (diameter ÷ 2)² × height × number of tubes

Esempio svolto: One 12 in × 4 ft sonotube: π × 0.5² × 4 = 3.14 ft³ ≈ 6 × 80 lb bags. An 8 in tube of the same height needs just 1.40 ft³ ≈ 3 bags.

Common quick references from this concrete calculator for sonotube forms: an 8 inch sonotube needs 0.35 ft³ per foot of height, a 10 inch 0.55 ft³/ft, a 12 inch 0.79 ft³/ft, and a 16 inch 1.40 ft³/ft.

That means a 4-ft-tall 12 inch sonotube takes about 6 × 80 lb bags, and an 8 sonotube of the same height about 3 bags. Filling several tube forms for a deck? Enter the count and the calculator totals bags across all of them.

Pour in one continuous lift where possible and rod or vibrate lightly to remove air pockets — tube forms show every void when stripped.

Domande frequenti

Domande comuni sulla sonotube concrete calculator.

How much concrete fills a 12 inch sonotube?

0.79 ft³ per foot of height. A 4 ft tube holds 3.14 ft³ — about 6 × 80 lb bags or 0.12 yd³.

How much concrete fills an 8 inch sonotube?

0.35 ft³ per foot. A 4 ft tube holds 1.40 ft³ — about 3 × 80 lb bags.

What sonotube sizes are standard?

6, 8, 10, 12, 14, 16, 18, 24, 30, 36 and 48 inch diameters, in lengths up to 12 ft. This tube calculator accepts any diameter.

Do sonotubes need a footing?

For decks and structures, yes — pour piers on a spread footing or use a flared-base form so loads distribute below frost depth.