Airflow Unit Converter (CFM / m³/h / L/s)
One airflow, every unit used across HVAC catalogues worldwide.
Japanese kit quotes m³/min, European m³/h or L/s, American CFM — three catalogues, one fan. Mixing them up has oversized many an AHU.
Formula
Airflow Unit Converter (CFM / m³/h / L/s) is a free cfm to m3h for HVAC designers, technicians and energy auditors — instant, accurate and 100% client-side, with the governing formula and reference shown next to the result so the number can be defended, not just quoted.
About Airflow Unit Converter (CFM / m³/h / L/s)
One airflow, every unit used across HVAC catalogues worldwide. The calculation implements 1 m³/h = 0.589 CFM = 0.278 L/s; 1 CFM = 1.699 m³/h (NIST SP 811). Japanese kit quotes m³/min, European m³/h or L/s, American CFM — three catalogues, one fan. Mixing them up has oversized many an AHU.
How to use Airflow Unit Converter (CFM / m³/h / L/s)
- 1Enter Airflow in m³/h.
- 2Read Cubic feet/min, Litres/second, m³/min instantly — no submit button needed.
- 3Need US units? Flip the SI/Imperial toggle and every field converts.
Why use Airflow Unit Converter (CFM / m³/h / L/s)?
- ✓Implements the standard formula — 1 m³/h = 0.589 CFM = 0.278 L/s; 1 CFM = 1.699 m³/h
- ✓Reference cited on-page: NIST SP 811
- ✓One-click SI ⇄ Imperial toggle — values convert in place, physics stays in SI
- ✓Runs entirely in your browser — nothing uploaded, free forever
Frequently asked questions
What formula does the Airflow Unit Converter (CFM / m³/h / L/s) use?+
It computes 1 m³/h = 0.589 CFM = 0.278 L/s; 1 CFM = 1.699 m³/h, per NIST SP 811. The formula is displayed under the result.
What should I keep in mind when using this calculator?+
Japanese kit quotes m³/min, European m³/h or L/s, American CFM — three catalogues, one fan. Mixing them up has oversized many an AHU.
Is this based on ASHRAE methods?+
The calculations follow the standard ASHRAE/ISHRAE formulations cited under the result, simplified where industry practice does the same. For permit-grade design, confirm with the full code procedure.
Is the Airflow Unit Converter (CFM / m³/h / L/s) free to use?+
Yes — completely free, no sign-up, no limits. It runs client-side in your browser, so inputs stay private and results are instant even on slow connections.
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