What Size Air Compressor Do I Need: A Simple Guide for Everyone

Have you ever asked yourself, “What size air compressor do I need?” I know I have! Picking the right size air compressor can be a little tricky, but don’t worry! In this article, I’ll help you figure out the perfect size air compressor for your needs. So, let’s dive right in and find the best air compressor for you!

Understanding Air Compressors

Before we start talking about sizes, it’s important to understand a little bit about air compressors. An air compressor is a machine that takes in air, compresses it, and stores it in a tank. The compressed air can then be used to power tools, inflate tires, or even paint.

There are two main types of air compressors: reciprocating (piston) and rotary (screw or vane). Reciprocating air compressors are more common for home use, while rotary air compressors are often used in industrial settings.

Key Factors to Consider

When trying to figure out what size air compressor you need, there are a few key factors to consider. Here they are:

  1. Air Pressure (PSI): PSI stands for “pounds per square inch” and is a measure of air pressure. Different tools require different amounts of air pressure to work properly.
  2. Air Flow (CFM): CFM stands for “cubic feet per minute” and is a measure of how much air flows through the compressor. The more CFM, the more tools you can run at the same time.
  3. Tank Size: The size of the air compressor’s tank determines how much compressed air it can store. A larger tank means you can run tools for longer periods of time before the compressor needs to refill.
  4. Power Source: Air compressors can be powered by electricity, gasoline, or diesel fuel. Make sure to choose a compressor that works with your available power source.

Determining Your Needs

Now that we know the key factors to consider, let’s figure out your specific needs. Here are some steps to follow:

  1. List your tools: Make a list of all the tools you plan to use with your air compressor. This might include things like nail guns, impact wrenches, air ratchets, or paint sprayers.
  2. Check the requirements: Look at the user manuals or labels on your tools to find their PSI and CFM requirements. If you can’t find this information, you can usually find it online or by contacting the manufacturer.
  3. Choose the highest requirements: To make sure your air compressor can handle all your tools, choose the one with the highest PSI and CFM requirements. This will ensure you have enough power and air flow for all your tools.
  4. Consider your usage: Think about how often you’ll be using your air compressor and how many tools you’ll be running at the same time. If you plan to use multiple tools at once, you may need a higher CFM rating. If you’ll be using your compressor frequently, you may want a larger tank to avoid constant refilling.
small air compressor inflating tire

Picking the Right Size Air Compressor

Now that you know your needs, it’s time to pick the right size air compressor. Here are some general guidelines to help you choose:

  1. Small Air Compressors (1-6 Gallon Tank): These compressors are great for light tasks, like inflating tires or using a brad nailer. They’re usually portable and easy to store, but they may not have enough power for larger tools.
  2. Medium Air Compressors (7-20 Gallon Tank): Medium-sized compressors are a good choice for most home and DIY projects. They can handle a variety of tools, like impact wrenches, paint sprayers, and air ratchets. They’re still somewhat portable but may be a bit heavier and larger.
  3. Large Air Compressors (21-30 Gallon Tank): These compressors are ideal for more demanding tasks and can handle multiple tools at once. They’re perfect for bigger projects, like automotive work or home renovations. Keep in mind that they’re usually heavier and take up more space.
  4. Extra-Large Air Compressors (31+ Gallon Tank): If you need a serious air compressor for heavy-duty or industrial use, an extra-large compressor is the way to go. They can power multiple tools simultaneously and are great for professional workshops or construction sites. Just be prepared for a hefty price tag and limited portability.

Don’t Forget the Accessories

Once you’ve chosen the right size air compressor, don’t forget to pick up some essential accessories. Here are a few items to consider:

  1. Air Hose: You’ll need a good-quality air hose to connect your tools to the compressor. Make sure it’s long enough to reach your work area and has the right fittings for your tools.
  2. Air Tool Oil: Keep your tools running smoothly by regularly lubricating them with air tool oil. This helps prevent rust and prolongs the life of your tools.
  3. Filters and Regulators: Filters help remove dust and debris from the compressed air, while regulators allow you to control the air pressure. Both are important for maintaining the performance of your tools.
  4. Quick-Connect Couplers: These handy connectors make it easy to switch between tools without turning off the air compressor. Just attach a coupler to each tool, and you’re good to go!


So there you have it! Now you know how to figure out what size air compressor you need. Just remember to consider the key factors, like PSI, CFM, tank size, and power source, and then match them to your specific needs. With the right size air compressor, you’ll be ready to tackle any project with ease and confidence.

About the Author Josh P.

I'm a computer geek by day, but I've been building and fixing stuff for as long as I can remember. I have a passion for DIY and woodworking projects and my wife considers me a tool junkie. One day I hope to finish the never-ending list of home improvement and remodeling jobs around the house.