Choose by job

Impact wrench work. Published demand 4 to 5 CFM average and 22 CFM at load. A burst tool, so a 6-gallon tank genuinely breaks lug nuts at 2.6 CFM. Whether that is enough depends entirely on whether your job is four wheels or a full brake job - and the page works through both.

Nailing. 0.5 CFM for a brad nailer, 1.8 for a 15-gauge finish nailer at 60 nails a minute, 2.5 for framing. This is the one job where the cheapest compressor on the shelf is the correct answer, which means you should choose on weight and noise instead.

Framing and roofing. Framing is published at 2.5 CFM. Roofing is published nowhere we could find, and rather than invent a figure we explain how to size for pace instead of peak. That gap in the data is real and we would rather name it.

Car tires. 2 CFM at 30 to 60 PSI - the easiest air job there is. Which is why the top pick on that page is not a compressor at all but a 4.75-pound 12V pump that lives in the car, because tires are rarely low next to your garage.

One theme runs through all four of these pages, and it is the thing that most often makes a correctly sized compressor feel inadequate. Ingersoll Rand specifies a 3/8-inch minimum hose internal diameter for its 1/2-inch impact wrench. Compressor accessory kits almost universally ship a 1/4-inch hose.

A tool starved by its hose behaves exactly like a tool starved by its pump: strong for a second, then soft. People spend several hundred dollars on a larger compressor to fix a problem a decent hose would have solved, and the upgrade does not fully fix it because the restriction is still there.

So before any job page tells you to buy a bigger compressor, it tells you to check the hose, the coupler chain and the regulator setting. That order is deliberate, it is cheapest-first, and it is frequently where the problem actually is.

They will not claim we have done the job. We have not timed a brake job on any of these compressors or framed a wall with any of these nailers. Every figure is a manufacturer-published specification or a published engineering reference, both linked, with the arithmetic shown.

They print the live Amazon price inside the buy control, refreshed daily and stamped with the date it was checked - and nothing at all when that figure cannot be verified.

And they will tell you when the honest answer is not a compressor. On the tire page the top pick is a 12V inflator. On several pages we point at an electric tool instead. If the best answer to your job is something we do not rank, saying so is the job.