Calculate the cubic feet of a room from length, width, and ceiling height. Use it for room volume, storage capacity, moving estimates, air purifier checks, and early ventilation planning.
Length
12 ft
Width
14 ft
Height
8 ft
Example room volume
1,344 ft³
A 12 × 14 ft room with an 8 ft ceiling contains 1,344 cubic feet of air space.
Enter inside dimensions in feet.
Optional: estimates CFM for ventilation planning. Use 0 if you only need room volume.
Quick room presets
Result
Formula: length × width × height. With the current inputs, the room volume is 1,344 cubic feet.
Floor area
168 ft²
Wall area
416 ft²
Cubic yards
49.78 yd³
Cubic meters
38.06 m³
Ventilation estimate
22.4 CFM
CFM = room cubic feet × air changes per hour ÷ 60. This is a planning estimate, not a substitute for HVAC code or equipment sizing.
Measure the inside length, inside width, and finished ceiling height in feet. Then multiply the three numbers together.
Room cubic feet = length (ft) × width (ft) × height (ft)
If one measurement is in inches, divide it by 12 first. For example, a 9 ft 6 in ceiling is 9.5 ft.
For a simple air-change estimate, use CFM = room ft³ × ACH ÷ 60. Example: 1,344 ft³ at 1 ACH needs about 22.4 CFM.
Use these as quick reference points before entering your exact room dimensions.
10 ft × 12 ft × 8 ft
960 ft³
27.18 m³ · 35.56 yd³
Useful for air purifier coverage, portable AC checks, and moving-box estimates.
16 ft × 20 ft × 9 ft
2,880 ft³
81.55 m³ · 106.67 yd³
A larger open room can have almost three times the air volume of a small bedroom.
10 ft × 10 ft × 8 ft
800 ft³
22.65 m³ · 29.63 yd³
Compare this number with packed item volume, not just floor area.
Room volume helps translate air changes per hour into a rough CFM target. Higher ceilings matter because they add air volume without changing floor area.
Cubic feet gives a better estimate than square feet when stacked boxes, wardrobes, shelving, or storage-unit height affect usable space.
Use interior dimensions to document room scale, compare rooms with vaulted ceilings, and sanity-check material or equipment assumptions.
Room cubic feet can support early planning, but final heating and cooling equipment should account for insulation, windows, climate, and local code.
Practical notes for measuring room volume correctly.
Multiply inside length by inside width by ceiling height. For example, a 12 ft × 14 ft room with an 8 ft ceiling is 12 × 14 × 8 = 1,344 cubic feet.
Use inside finished dimensions for room air volume, storage space, air purifier coverage, and moving estimates. Outside dimensions include wall thickness and usually overstate the usable room volume.
Use the average ceiling height when the room shape is simple. For complex vaulted rooms, split the space into rectangular and triangular sections, calculate each volume, then add them together.
No. Cubic feet and CFM estimates are useful starting points, but HVAC sizing also depends on insulation, windows, leakage, sun exposure, equipment efficiency, occupancy, climate, and building code.
From cubic meters to cubic feet, compare volumes quickly with clear formulas and fast results.