The exact factors
One cubic foot is 0.028 316 85 m³, which is 28.316 85 litres, because one cubic metre is exactly 1,000 litres. Going the other way, one litre is 0.035 315 cubic feet and one cubic metre is 35.315 cubic feet.
For linear dimensions, 1 foot is exactly 0.3048 m and 1 inch is exactly 25.4 mm. If you measure a cabinet inside in centimetres, width × depth × height in cm divided by 1,000 gives litres directly.
- Cubic feet → litres: multiply by 28.317
- Litres → cubic feet: divide by 28.317 (or multiply by 0.035 31)
- Cubic feet → cubic metres: multiply by 0.028 32
- Cubic metres → litres: multiply by 1,000
Quick table: cubic feet to litres
| Cubic feet | Litres | Cubic feet | Litres |
|---|---|---|---|
| 1 | 28.3 | 12 | 339.8 |
| 2 | 56.6 | 15 | 424.8 |
| 3 | 85.0 | 18 | 509.7 |
| 4 | 113.3 | 20 | 566.3 |
| 5 | 141.6 | 23 | 651.3 |
| 6 | 169.9 | 25 | 707.9 |
| 7 | 198.2 | 30 | 849.5 |
| 8 | 226.5 | 35 | 991.1 |
| 10 | 283.2 | 50 | 1,415.8 |
Quick table: litres to cubic feet
| Litres | Cubic feet | Litres | Cubic feet |
|---|---|---|---|
| 100 | 3.53 | 500 | 17.66 |
| 150 | 5.30 | 600 | 21.19 |
| 200 | 7.06 | 750 | 26.49 |
| 250 | 8.83 | 1,000 | 35.31 |
| 300 | 10.59 | 1,200 | 42.38 |
| 400 | 14.13 | 1,500 | 52.97 |
Cold rooms: from feet to cubic metres
Walk-in cold rooms are often described by internal dimensions in feet. Multiply the three dimensions to get cubic feet, then multiply by 0.028 32 for cubic metres. Make sure everyone is talking about internal dimensions; panel thickness on each side makes the outside noticeably bigger.
Example: a builder quotes a room as 10 × 8 × 8 ft outside with 100 mm (about 0.33 ft) panels. Inside, that is roughly 9.34 × 7.34 × 7.67 ft (ceiling panel only, no floor panel assumed) = 526 cu ft, or 14.9 m³, not the 18.1 m³ the outside size suggests.
| Internal size (L × W × H, ft) | Cubic feet | Cubic metres |
|---|---|---|
| 6 × 6 × 7 | 252 | 7.14 |
| 8 × 6 × 7 | 336 | 9.51 |
| 8 × 8 × 8 | 512 | 14.50 |
| 10 × 8 × 8 | 640 | 18.12 |
| 10 × 10 × 9 | 900 | 25.49 |
| 12 × 10 × 9 | 1,080 | 30.58 |
Worked examples
Comparing two quotes: supplier A offers a 23 cu ft upright, supplier B a 650 L upright. 23 × 28.317 = 651.3 L, so the two are effectively the same gross size. The real comparison is shelf count, shelf width and whether both figures are gross or net.
Checking a brochure: an upright measures 1,240 mm wide, 700 mm deep and 1,900 mm high inside the liner (assumed figures). 124 × 70 × 190 cm = 1,649,200 cm³ ÷ 1,000 = 1,649 L of empty box, or 58.2 cu ft. A listed capacity close to this is a gross figure; usable space after shelves, evaporator and air gaps will be lower.
Rounding and wording traps
- Using 28 instead of 28.317 understates litres by about 1.1%. Small, but enough to make two identical cabinets look different on paper.
- Using 30 litres per cubic foot as mental shorthand overstates by about 6%. Fine for a rough idea, not for a purchase comparison.
- Gross volume is the empty box. Net or storage volume excludes parts you cannot use. Ask which one a figure is before converting it; converting does not change what it measures.
- Cold room quotes sometimes give external size. Subtract twice the panel thickness from each dimension before working out storage volume.
Frequently asked questions
- How many litres is a 10 cubic feet freezer?
- 10 × 28.317 = 283.2 litres. Check whether that is the gross or net volume; a chest freezer usually also loses some space to the compressor step at one end.
- Why do Indian brochures mix litres and cubic feet?
- Litres are the metric unit used on most labels in India, while cubic feet persist from imported equipment and older trade habits. The conversion is exact, so convert everything to one unit before comparing.
- How many cubic feet and litres are in one cubic metre?
- One cubic metre is exactly 1,000 litres and about 35.31 cubic feet. So a cold room quoted at 14.5 m³ inside is about 512 cu ft, which is the familiar 8 × 8 × 8 ft room, and 14,500 litres of empty space.
