A 14 in Sonotube 4 ft long holds 4.28 cu ft of concrete — 8 × 80-lb bags or 10 × 60-lb bags.
| Per column | 60-lb | 80-lb |
|---|---|---|
| This calculator (geometry) | 10 | 8 |
| Bag | Bags | Est. cost |
|---|---|---|
| 40 lb · 0.3 ft³ | 16 | — |
| 50 lb · 0.375 ft³ | 13 | — |
| 60 lb · 0.45 ft³ | 11 | $53.35 |
| 80 lb · 0.6 ft³ | 8 | $51.76 |
Typical U.S. big-box prices checked 2026. Tap any price to enter your store's.
| Length | Cu ft per tube | 80-lb per tube | 60-lb per tube |
|---|---|---|---|
| 2 ft | 2.14 | 4 | 5 |
| 3 ft | 3.21 | 6 | 8 |
| 4 ft ← | 4.28 | 8 | 10 |
| 5 ft | 5.35 | 9 | 12 |
| 6 ft | 6.41 | 11 | 15 |
| 8 ft | 8.55 | 15 | 20 |
Round forms are cylinders: area = π × radius². A 14 in tube has a 7 in radius, so π × 7² = 153.9 sq in ÷ 144 = 1.069 sq ft. Multiply by the length in feet for cubic feet.
4.28 cu ft ÷ 0.6 cu ft per 80-lb bag = 7.13, and ÷ 0.45 per 60-lb bag = 9.5. Tube tables round each tube up — here that leaves most of a bag over, so on several tubes round the total instead.
At 0.17 yd³ this is a bag job: a truck's 1 yd minimum plus fees would cost about $485.
The full method, material data and tips are on the main sonotube & column concrete calculator page.