1. Pressure Requirements - What pressure does your application require? (this information is normally stamped on the air tool being used with the air compressor).
2. CFM Requirements - How much CFM does the air tool need to operate at peak efficiency? (this information is also normally stamped on the air tool).
3. Number of air tools being operated - How many tools are you planning to run simultaneously with the air compressor?
When shopping for an air compressor it's important to keep in mind that a larger CFM compressor doesn’t necessarily mean a more powerful compressor. CFM tells you how much air a compressor can deliver, while PSI (Pounds per Square Inch) tells you how much power a compressor has. To get real world measurements of compressor power output (SCFM) a compressor pump must be spinning under load at its rated PSI to get actual volume output in CFM.