The 15 Best Air Compressors for Home Use

PSI, CFM, and Other Confusing Air Compressor Jargon

One glance at an advertisement for an air compressor can leave many of us scratching our heads. “What do I need?” we ask, as we puzzle over strange terms like “PSI” and “CFM”. Let’s quickly cover the basics of these terms, so that you can use them to guide your selection.

Maximum Internal PSI versus PSI Output

The Pounds per Square Inch number (PSI) can represent the compressed air pressure inside the tank as well as the pressure with which the air is released into the hose. When we are talking about the internal pressure, PSI represents just how tightly the system is able to pack air into that tank.

You might assume that higher PSI numbers are, generally, better, and for the most part you would be correct. Beware, though, because many companies will try to fool you with the PSI output numbers they provide. The “maximum PSI” rating listed on most machines isn’t actually the pressure with which air is forced from the unit – it is the pressure maintained inside.

Try to find a machine that has a significantly higher maximum internal PSI numbers than its maximum output PSI; as long as the tank pressure is higher than the pressure in the hose, you will have enough air available. If not, you’ll have to wait around for the motor to catch up to the work you’re performing.

For home use and in small workshops, the best air compressor is one with a max PSI of at least 120 – the average air tool is designed to operate at an output of at least 90 PSI.

Recommended CFM and Its Relation to PSI

The difference between PSI and CFM is confusing to most people. Instead of CFM (cubic feet per minute), some manufacturers use SCFM (standard cfm) instead of CFM (cubic feet per minute), although SCFM is mostly used for air tools.

To keep things simple, consider CFM to be a way of measuring “fast” whereas PSI measures “hard”. The PSI represents how much force the compressed air has as it comes out of the unit, whereas the CFM represents how much air comes out within some amount of time.

For any given air compressor, the CFM will drop as the PSI rises, although some will allow you to make adjustments via the compressor’s regulator.

When it comes to using tools, some need a lot of air but not necessarily a lot of force. This means that a high CFM rating and a low PSI rating work well for things like airbrushing, whereas a mid-range CFM rating and a high PSI rating are great for nail guns, paint sprayers, and other high-powered tools.

In fact, you will often find that the packaging and specification pages for air compressors show more than one CFM and PSI combination. For example, the California Air Tools 5510SE is openly advertised as having 3.10 CFM at 40 PSI and 2.20 CFM at 90 PSI, helping you to ensure that it will meet the needs of whichever types of tools you intend to use.

It’s also important to note that actual CFM performance will vary according to things like barometric pressure and altitude, so anyone living at altitudes different from most of us will need to take these factors into account.

What Air Tool to Use?

Before going out and looking at options, you need to figure out what kind of power tools you will be using with it. Purchase those tools, or look at ones you already own, and figure out what CFM and/or PSI ratings they call for. Not every air tool will work well with every compressor, so don’t neglect this part of making your decision.

If you plan to use your machine with tools that require different CFM and PSI ratings, you will have to buy an compressor that comes with an air pressure regulator. A pressure regulator lets you adjust the PSI output which, in turn, changes the CFM output.

How Does Horsepower Factor In?

As with many other tools and appliances, horsepower is a major consideration. In fact, a lot of people consider this to be the most important factor when making their choice. However, horsepower is definitely not the only thing to think about when purchasing an air compressor. In fact, it falls somewhere near third on that list.

It doesn’t matter how strong the motor of your compressor is if it cannot actually run the tools you need to operate. The PSI and CFM ratings of your machine will certainly reflect the horsepower and strength of the motor to a certain degree, but these will always be your primary considerations.

At the end of the day, though, when all other things are equal, higher horsepower motors are going to be preferable to their weaker counterparts. This is because stronger motors usually last longer and can also run for greater stretches of time without overheating and breaking down. They also tend to be capable of supplying you with high PSI and high CFM simultaneously.

Air Compressor Portability

Depending on the type of work you intend to do with your air compressor, it may be the case that you need to drag it around from time to time. If this sounds like even a remote possibility for you, you should consider a machine’s overall size, weight, and the ease with which it can be transported.

Despite the size of an air compressor and its metal exterior, the fact that it is filled with air makes it surprisingly lightweight. The range of weights for similar machines is rather large, though, simply because stronger motors are heavier than weaker ones.

If, therefore, you want something with a larger tank and a strong motor, you may want to look for something like the Makita Mac 5200, which comes with wheels for increased portability.