A Future Business Media publication
Air Compressor Mag

Independent air compressor buying guides, reviews and how-tos.

Latest guides

Air Compressor Repair: Fix It by Symptom Repair & Maintenance Air Compressor Repair: Fix It by Symptom Symptom-based air compressor repair: won't build pressure, won't start, won't shut off, trips the breaker, leaks, or oil in the line. Safe fixes. 12 min read Air Compressor Oil: Which Type, How Often, and How to Change It Repair & Maintenance Air Compressor Oil: Which Type, How Often, and How to Change It Use non-detergent SAE 30 (ISO 100) in most piston compressors, skip motor oil, and change it on hours not guesses. Named products and full steps. 11 min read Tools Air Compressor Tools & Calculators Free air compressor calculators: work out the CFM and tank size you need, how long a tank lasts between cycles, and convert airflow and pressure units. 1 min read Air Compressor Size Calculator: What CFM Do You Need? Tools Air Compressor Size Calculator: What CFM Do You Need? Free calculator: pick the air tools you'll run and get the minimum CFM and tank size your air compressor needs, with headroom built in. Best Air Compressor for a Home Garage (2026): Picks by What You Actually Run Buying Guides Best Air Compressor for a Home Garage (2026): Picks by What You Actually Run Best home garage air compressors by CFM at 90 PSI: top pancake, quiet pick for attached garages, budget, and impact-wrench choices, with honest limits. 9 min read What Size Air Compressor Do I Need? A Plain Sizing Guide Buying Guides What Size Air Compressor Do I Need? A Plain Sizing Guide Find your tool's CFM at 90 PSI, multiply by 1.5, and match a tank. Nailing needs 2 to 4 CFM, air tools 5 to 10 plus. Full chart inside. 9 min read

Buying an air compressor sounds simple until you start shopping. Suddenly you are weighing CFM against PSI, gallons against horsepower, and oil-free against oil-lubricated, all while the listings shout numbers that may or may not matter for what you actually want to do.

Our job is to cut through that. Every guide here is written to answer one real question, in order: what do you need, which model fits, and how do you keep it working. No spec-sheet copy-paste, no filler.

Start with the job, not the machine

The single most useful question is “what will I run with it?” A tire and an air mattress need almost nothing. A brad nailer needs a little more. A framing nailer, impact wrench, or sander needs real, sustained airflow. Match the tool’s air demand (its CFM rating at 90 PSI) first, then pick tank size and portability to suit how you work. The guides below walk through each of those decisions.

How an air compressor works

Air is drawn in through a filter, compressed by the pump, stored in the tank, regulated to a working pressure, then delivered to your tool.
The air path, from intake to tool. A pressure switch cycles the pump to keep the tank topped up.

Every compressor follows the same path: it draws air through a filter, the pump compresses it, the tank stores it under pressure, and a regulator drops it to the working pressure your tool needs. A pressure switch starts and stops the pump to keep the tank between its cut-in and cut-out pressures, which is why your compressor kicks in now and then while you work.