Air Compressor Size Calculator: What CFM Do You Need?
Pick the tools you plan to run and we'll work out the minimum airflow (CFM at 90 PSI) and a sensible tank size. The single most common mistake is buying on tank size or horsepower; CFM is what decides whether a tool works.
Which tools will you run?
Tools draw air in short bursts, so we add 50% headroom to the figure above to cover duty cycle and pressure drop. If you expect to run a tool continuously (sanding, sandblasting, spraying), size up further.
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