What is a Cubic Foot?
The cubic foot is the American standard for HVAC capacity, natural gas billing, and refrigerator volume.
Overview
The cubic foot equals approximately 28.317 liters (or exactly 1,728 cubic inches) and is the American standard volume unit for HVAC capacity, natural-gas billing, refrigerator interior volume, and bulk material like concrete or mulch. American gas utilities measure delivered gas in 'CCF' (hundred cubic feet) or 'MCF' (thousand cubic feet), even when the customer thinks in terms of monthly bills. Refrigerators are advertised by their interior cubic-foot capacity (typical home unit: 18–25 ft³). Air-conditioning systems are rated in CFM (cubic feet per minute) airflow. Concrete is sometimes priced by the cubic yard (27 ft³), and mulch and topsoil are often sold by cubic foot bags. The cubic foot relates to the cubic yard (27 ft³ = 1 yd³), the cubic inch (1,728 in³ = 1 ft³), the cubic meter (1 ft³ ≈ 0.0283 m³), and the gallon (1 ft³ ≈ 7.481 US gal).
Convert Cubic Foot to all units
Live resultRelationship to Other Volume Units
1 ft³ equalsVisual reference for how the cubic foot relates to other volume units. Each row links to the full converter for that pair.
When Is the Cubic Foot Used?
- US air-conditioning and ventilation flow (CFM)
- US natural gas consumption
- Refrigerator and freezer capacity in the US
A typical US fridge is 20 cu ft (566 L). US HVAC flow rated in CFM. US residential gas billed per 100 cu ft (CCF).
Tips for Using the Cubic Foot
- 1 ft³ = 28.317 L = 0.0283 m³.
- CFM to m³/h: multiply CFM by 1.699.
- 1 m³ ≈ 35.3 ft³.
Common Mistakes
- Confusing ft³ with ft² in US real-estate contexts.
- Using 28 L instead of 28.32 L in precision HVAC calculations.
- Mixing CCF (100 cubic feet) with CFM (cubic feet per minute) on utility bills.