Air Hose Size & Pressure Drop Calculator: Will Your Hose Choke the Tool?
Your compressor can be the right size and still leave a tool gasping, because a long or narrow hose bleeds pressure on the way to the tool. Enter your hose length, its inside diameter and your tool's air draw, and we'll estimate the pressure you actually have at the coupler. The hose bore matters far more than its length: dropping from 3/8\" to 1/4\" can cut your usable pressure dramatically.
Estimate the pressure drop down your hose
Pressure drop rises with the square of airflow and falls steeply as the bore widens, so airflow-hungry tools (sanders, grinders, spray guns) suffer most on a thin hose. If the figure above looks bad, the cheapest fix is almost always a wider hose, not a bigger compressor.
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