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CFM to m³/h Airflow Converter

Type a value in any box — the others update live. Covers CFM, cubic metres per hour, litres per second, cubic metres per second and air mass flow.

Conversion factors

1 CFM = 1.699 m³/h = 0.4719 L/s = 0.0004719 m³/s. Air mass flow uses ρ ≈ 1.2 kg/m³ at 20°C, so 1 m³/h ≈ 1.2 kg/h. These are the units you meet constantly when reading a heat exchanger datasheet or sizing duct.

Frequently asked questions

CFM or m³/h — which should I specify?
North American equipment is rated in CFM; European and most Asian standards use m³/h. Convert with this tool so you can compare cores on the same basis.
Does density change the mass flow?
Yes — hot or high-altitude air is lighter, so a given volume flow carries less mass and less energy. For energy calculations always use mass flow (kg/h), not volume.
Where do I use this with other tools?
The airflow value feeds the savings, payback and sizing calculators.
Free converter by Zibo Qiyu — contact us for air-to-air heat exchanger selection.