How to Convert Cubic Feet to Liters
Converting cubic feet to liters is an important volume conversion that bridges the imperial volumetric measurement used in the United States and United Kingdom with the metric standard adopted worldwide. The cubic foot (ft cubed) is a unit of volume defined as the space occupied by a cube measuring one foot on each side, commonly used in construction, HVAC systems, shipping, and real estate. The liter (L) is the metric unit for everyday volume measurement, used globally for liquids, gases, and container capacities. One cubic foot equals approximately 28.3168 liters. This conversion is essential for engineers designing ductwork and ventilation systems, shipping professionals calculating container volumes, aquarium hobbyists sizing tanks, and construction workers estimating material quantities. The cubic foot remains prevalent in American building codes, natural gas billing, and refrigerator sizing, making its conversion to liters necessary for international collaboration and metric-standard compliance.
Conversion Formula
To convert cubic feet to liters, multiply the volume in cubic feet by 28.3168. This factor is derived from the relationship between feet and meters: one foot equals exactly 0.3048 meters, so one cubic foot equals 0.3048 cubed = 0.028316846592 cubic meters. Since one cubic meter equals 1,000 liters, one cubic foot equals approximately 28.3168 liters. The precise value is 28.316846592 liters per cubic foot.
Liters = Cubic Feet × 28.3168
5 cubic feet = 141.584 liters
Step-by-Step Example
To convert 5 cubic feet to liters:
1. Start with the value: 5 cubic feet
2. Multiply by the conversion factor: 5 × 28.3168
3. Calculate: 5 × 28.3168 = 141.584
4. Result: 5 cubic feet = 141.584 liters
This is equivalent to roughly 141 standard 1-liter water bottles, or about 37 US gallons.
Understanding Cubic Feet and Liters
What is a Cubic Foot?
The cubic foot is an imperial and US customary unit of volume based on the foot, which has ancient origins tracing back to civilizations that used the human foot as a length standard. The modern international foot was standardized in 1959 as exactly 0.3048 meters, giving the cubic foot a precise volume of 0.028316846592 cubic meters. The cubic foot has been used for centuries in English-speaking countries for measuring storage space, cargo volumes, and building dimensions. It remains the standard unit for expressing refrigerator capacity, natural gas volume, and HVAC airflow rates in the United States, though many industries are gradually transitioning to metric units.
What is a Liter?
The liter was created in 1795 as part of the revolutionary French metric system, originally defined as the volume of one kilogram of pure water. The name "liter" derives from "litron," an older French unit. After a redefinition in 1901 tied it to water mass more precisely, the 1964 redefinition simplified the liter to exactly one cubic decimeter (0.001 cubic meters). The liter is accepted for use with the SI system and has become the most widely used volume unit for everyday measurements worldwide. Its clean decimal relationship with cubic meters and milliliters makes it the practical choice for expressing volumes ranging from beverage containers to industrial tanks.
Practical Applications
Cubic feet to liters conversion is widely used in the HVAC industry when translating airflow specifications and duct sizes between imperial and metric standards. Aquarium enthusiasts convert tank volumes from cubic feet or gallons to liters for international equipment and treatment products. The shipping and logistics industry uses this conversion when calculating container volumes for international freight. Natural gas companies often meter consumption in cubic feet but may need to report in metric units for international comparison. Refrigerator and freezer capacities listed in cubic feet are converted to liters for international product labeling.
Tips and Common Mistakes
A common mistake is confusing cubic feet with square feet. Cubic feet measure three-dimensional volume, while square feet measure two-dimensional area. Another frequent error is using the linear foot-to-meter conversion factor (0.3048) instead of cubing it for volume conversion. The volume factor of 28.3168 is the cube of the linear factor, and using the wrong one leads to massive errors. When converting between cubic feet and gallons, remember that 1 cubic foot equals approximately 7.481 US gallons. Always double-check which unit system your source data uses before performing conversions.
Frequently Asked Questions
One cubic foot equals approximately 28.3168 liters. This is derived from the exact relationship that 1 foot = 0.3048 meters, so 1 cubic foot = 0.3048^3 cubic meters = 0.028317 cubic meters = 28.317 liters. This is a substantial volume, roughly equivalent to 7.5 US gallons.