The conversion
One cubic foot contains 28.316846592 liters. For a flow measured per minute, multiply CFM by this factor to obtain L/min. Divide L/min by the same factor to return to CFM. The time unit is unchanged, so no additional factor of 60 is needed.
An illustrative 5 CFM specification converts to about 141.6 L/min. A 300 L/min specification converts to about 10.59 CFM. Keep a sensible number of decimal places: the converted result is not more precise than the original measurement.
Copy the full specification
Suppose one fictional compressor is labeled 150 L/min at 90 PSI and another is labeled 5 CFM at 90 PSI. Converting the first value produces approximately 5.30 CFM, making the numerical comparison easier. That comparison still depends on both figures describing the same kind of delivered airflow under comparable reference conditions.
A catalog might instead describe piston displacement, free-air delivery, standard flow or a tool’s average consumption. Similar-looking units do not make those quantities equivalent. Preserve the original label, rated pressure and any stated temperature or reference conditions beside the converted number.
Use the result in a match
First confirm whether the number belongs to the compressor’s output or the tool’s demand. Then confirm the operating pressure and consumption basis. Finally, compare the normalized values. A 40 PSI compressor rating cannot be relabeled as a 90 PSI rating simply by changing its units.
This converter performs a geometric unit conversion only. It does not correct gas volume for temperature, humidity or absolute pressure. When two sources use different standard conditions and those differences are material, obtain comparable data before treating the apparent margin as usable capacity.
Changing CFM to L/min changes the unit. It does not turn displacement, average flow or free-speed consumption into delivered air.