Convert Cubic Feet to Cubic Meters

About Cubic Feet to Cubic Meters Conversion

Cubic feet (cu ft or ft³) and cubic meters (m³) are units of volume from different measurement systems. The cubic foot is built from the foot used in U.S. customary and most imperial uses, while the cubic meter is an SI unit used internationally for freight, room volumes, bulk materials, and engineering calculations. Because a cubic meter is much larger than a cubic foot, the numerical value becomes smaller when cubic feet are rewritten in cubic meters.

The conversion is exact when the foot means the international foot: 1 ft = 0.3048 m exactly, so 1 ft³ = (0.3048 m)³ = 0.028316846592 m³ exactly. To convert cubic feet to cubic meters multiply by 0.028316846592. The reverse direction uses the approximate reciprocal 1 m³ = 35.31466672 ft³ approximately.

Exact Relationship

Volume scales with the cube of length. That is why the exact foot-to-meter relationship must be cubed rather than copied directly from the linear conversion. One cubic foot is the volume of a cube 1 foot on each side; replacing each side with 0.3048 meter gives a cube 0.3048 meter on each side.

Cubing the exact length definition gives 1 ft³ = 0.3048 x 0.3048 x 0.3048 m³ = 0.028316846592 m³ exactly. This applies to the modern international foot used for ordinary commercial and engineering work. Older U.S. survey-foot documents can differ slightly, mostly in legacy surveying and mapping rather than everyday (smaller) volume conversion.

Example Calculation

Suppose a storage room, hopper, or duct volume is 250 cubic feet and you need the value in cubic meters. Multiply 250 by 0.028316846592.

250 ft³ x 0.028316846592 m³/ft³ = 7.079211648 m³

Rounded to two decimal places, that is 7.08 m³. The number is smaller because the cubic meter is the larger unit.

Example for Freight and Storage

International freight quotes and warehouse specifications are often stated in cubic meters even when crate dimensions were first measured in feet. A crate measuring 4 ft x 4 ft x 3 ft has a volume of 48 ft³. Converting gives 48 x 0.028316846592 = 1.359208636416 m³, which may be rounded and quoted as 1.36 m³.

That kind of rounding is common in shipping and storage because charges may be based on tenths or hundredths of a cubic meter. The physical volume does not change, but the degree of rounding can affect paperwork, rate comparisons, or whether two quoted capacities are really the same space stated in different units.

Common Benchmarks

These reference values help you benchmark common cubic volumes between cubic feet and cubic meters.

Cautions

Do not use the linear factor 0.3048 by itself when converting volume. That converts feet to meters, not cubic feet to cubic meters. Volume must use the cubed factor 0.028316846592.

Be careful not to confuse volume with flow rate. Cubic feet per minute (cfm) and cubic meters per hour are rates, not static volumes, and they require time-unit conversion as well.

For gases, a value in cubic feet may also depend on stated temperature, pressure, or standard conditions. The mathematical unit conversion is still valid, but two gas volumes measured at different conditions are not directly comparable just because both are written in cubic feet or cubic meters.

Reference

• NIST Handbook 44 (2026), Appendix C. General Tables of Units of Measurement
• NIST, U.S. Survey Foot: Revised Unit Conversion Factors
• BIPM, SI base unit: metre (m)