Article — Cubic Feet to Cubic Meters Converter
Cubic feet to cubic meters conversion: the exact 0.0283168 factor
One cubic foot equals 0.0283168 cubic meters, exactly. The factor is the cube of the linear foot-to-meter factor: 0.3048³ = 0.028316846592. To convert cubic feet to cubic meters, multiply by 0.0283168; to convert cubic meters to cubic feet, multiply by 35.3147. The relationship is exact because the underlying linear factor is exact.
The two units sit at the heart of international shipping, construction, and HVAC engineering. SI countries quote concrete deliveries, container volumes, and air handler ratings in cubic meters. The United States and parts of the UK use cubic feet for the same jobs. International trade crosses the divide on every bill of lading.
The cubic feet to cubic meters rule
The rule is exact: 1 ft³ = 0.028316846592 m³. The factor comes from cubing the international foot definition: (0.3048 m)³ = 0.028316846592 m³. The reciprocal 1 m³ = 35.31466672 ft³ falls out by inversion. Both factors are exact in principle, though they are usually displayed truncated.
For mental math, 1 m³ ≈ 35 ft³ is accurate to 0.4%, fine for rough estimates. The 1:35 ratio is easy to apply: a 5 m³ load is roughly 175 ft³; a 1000 ft³ space is roughly 28.6 m³. For invoice-grade conversions, use the full 35.3147 factor.
What is a cubic foot?
A cubic foot is the volume of a cube with sides exactly 1 foot (0.3048 m) long. It contains 1728 cubic inches (12³ = 1728), 28.3168 liters, or about 7.48 US liquid gallons. The cubic foot is the standard imperial volume unit for medium-scale measurements in the United States and Canada.
Refrigerator capacity is the most common everyday context. A standard US top-freezer refrigerator holds 18 to 22 ft³ (510 to 623 L); a side-by-side runs 24 to 28 ft³. Storage units, shipping cartons, and natural gas flow rates also use cubic feet as the base unit.
What is a cubic meter?
A cubic meter is the SI derived unit of volume. It is the volume of a cube with sides exactly 1 meter long, equal to 1000 liters or 35.3147 cubic feet. The cubic meter (m³, sometimes written CBM in shipping) is the standard metric volume unit for construction, freight, and HVAC.
One cubic meter of fresh water has a mass of almost exactly 1000 kg (1 metric tonne) at 4°C, the temperature at which water reaches maximum density. The relationship was deliberate: the original 1795 definition of the kilogram set its mass equal to one liter of water, and the cubic meter is 1000 liters. The link survives in modern engineering shortcuts: 1 m³ of water = 1 tonne, to within 0.04% at room temperature.
The cubic feet to cubic meters formula
One factor and its reciprocal:
ft³ × 0.0283168 = m³m³ × 35.3147 = ft³1 m³ = 1000 L = 264.17 US gal1 ft³ = 28.3168 L = 7.4805 US galDerivation comes from cubing the linear factor. Because 1 ft = 0.3048 m exactly, 1 ft³ = 0.3048³ m³. The cube of an exact value is exact, so the volumetric conversion inherits the precision of the linear definition.
Cubic feet to cubic meters in shipping
Ocean freight is priced by cubic meter (CBM) or metric ton, whichever is higher. The standard ISO 20-foot dry container has an internal volume of 33.2 m³ (1172 ft³); a 40-foot container holds 67.7 m³ (2390 ft³); a 40-foot high-cube holds 76.0 m³ (2685 ft³). Quoting volumes in CBM lets carriers compute price per unit volume across all units.
Air freight uses dimensional weight (also called volumetric weight) to discourage low-density cargo from taking up cabin space. The IATA conversion is 1 m³ = 167 kg of dimensional weight, so a 5 m³ shipment is billed as 835 kg even if it physically weighs 200 kg. Couriers like FedEx and DHL apply similar formulas to small parcels.
For a shipping quote, compute the volume in cubic meters first, then convert if needed. A box of 50 cm × 40 cm × 30 cm = 0.06 m³ = 2.12 ft³. Most carriers want CBM; converting box-by-box to ft³ adds rounding error that compounds over a pallet.
Cubic feet to cubic meters in construction
Concrete is the most-converted construction material. Ready-mix is sold by the cubic yard in the US (1 yd³ = 27 ft³ = 0.7646 m³) and by the cubic meter everywhere else. A standard concrete truck holds 8 to 11 m³ (10 to 14 yd³, or 282 to 388 ft³). Pouring volume is computed in the local unit, then ordered with a 5% to 10% margin for spillage and over-excavation.
Excavation and earthwork follow the same pattern. A foundation trench 10 m × 1 m × 1.5 m holds 15 m³ of soil (530 ft³). Bulking factor pushes the loose volume higher; clay can swell by 30% from in-place to loose, so 15 m³ in the ground becomes 19.5 m³ on the truck.
Cubic feet to cubic meters conversion table
The most-searched values, with practical context.
- 1 ft³ = 0.0283 m³ (28.3 L, microwave volume)
- 10 ft³ = 0.283 m³ (apartment mini-fridge)
- 20 ft³ = 0.566 m³ (standard refrigerator)
- 100 ft³ = 2.832 m³ (storage locker)
- 27 ft³ = 0.7646 m³ (cubic yard, US concrete)
- 1000 ft³ = 28.32 m³ (reference 10×10×10 ft cube)
- 1172 ft³ = 33.2 m³ (ISO 20-ft container)
- 2390 ft³ = 67.7 m³ (ISO 40-ft container)
- 2685 ft³ = 76.0 m³ (ISO 40-ft high-cube)
- 35,315 ft³ = 1000 m³ (Olympic pool roughly)
Common cubic-feet-to-cubic-meter mistakes
Using the linear factor instead of the cube. A frequent slip is to multiply ft³ by 0.3048 instead of 0.0283168. The cube of an exact linear factor is exact too, but it is much smaller. An order of magnitude error follows: a 100 ft³ box becomes 30.48 m³ instead of the correct 2.83 m³.
Confusing cubic feet with square feet. Volume is a length cubed; area is a length squared. A 100 ft² floor and a 100 ft³ box have nothing in common. The notation difference (³ vs ²) is the only typographic clue, easy to miss in a handwritten note.
One cubic yard equals 27 cubic feet, but only 0.7646 cubic meters. Many US concrete suppliers quote in cubic yards; many international suppliers quote in cubic meters. Ordering 10 cubic yards (7.65 m³) is not the same as ordering 10 cubic meters (13.08 yd³). The 30% gap is the most expensive imperial-versus-metric error on a construction site.
Rounding before cubing. If you round 1 ft = 0.305 m and then cube to get the volume factor, the result is 0.02835 m³, which is 0.07% high. The full 0.3048 cubed gives the correct 0.0283168. For large volumes the error grows: a 10,000 ft³ shipment converted with 0.305 becomes 283.5 m³ instead of the correct 283.2 m³.
Mixing CBM and cubic feet on the same invoice. Freight forwarders may quote in CBM, in cubic feet, or in both. Reading 33 CBM as 33 ft³ would understate a 20-foot container by a factor of 35. Always confirm the unit label, especially when papers cross from a metric to an imperial market.