How many gallons of air compressor do I need?

How many gallons of air compressor do I need?
Many hobbyists or DIY enthusiasts who are a novice in this niche frequently ask for air compressor’s right size to buy. Sure, there are multiple air compressors in the market, and they come in different sizes and shapes, so you’ll have to identify which one is compatible with your air tool. Right, let’s jump into the question that cracks heads out here, how many gallons of air compressor do I need?

If this is a question that has been crisscrossing your mind of late, you are in the right place. Okay! You’ll have to bring into play many factors when evaluating the correct number of gallons for your tool. It is evident that the bigger your tank’s capacity, the more the number of tools you can operate. What’s vital is for you to check your tool’s rating and confirm if they are compatible with the air compressor ratings. That entails the pressure ratings, generally designated in pounds per square inch (PSI), and the airflow in cubic feet per minute (CFM). For proper estimation, multiply the tool’s CFM by a safety factor of 1.5 to determine the compressor’s size that can run it. In short, the air compressor should provide enough pressure and airflow to run the tool effectively. Before we proceed, let’s jump into the advantages of air tools:

Advantages of Air Tools

The person who invented that compressed air is an excellent source of energy deserves much credit. Imagine forcing air into a tank at an absolute pressure, which we use to run our tools. That’s incredible! Right? Air tools have tremendous advantages over its competitors. A garage warrior should identify the best kind of air tools to run projects smoothly. Here are the benefits air tools have over electric nor cordless tools:

  • Air tools possess more power than electric tools in many cases
  • Pneumatic tools are lightweight, thus reduces operators fatigue
  • They have longer service life compared to electric tools
  • The devices ensure reduced heat output
  • They exempt electric shock or fire hazard
  • Pneumatic tools are cheaper compared to their counterparts

However, before operating any air tool, you’ll have to arm yourself with an air compressor. And since it is the source of power for the tool, you have to get the size right for smooth operation. Anyway, before deciding on your air compressor size, ask yourself these questions:

What types of tasks am I going to be doing?

This question is crucial since it will determine the range of power that an air compressor can provide. The tasks include home upgrades or automotive repair, more significant construction projects, or frequent maintenance projects. Apparently, you’ll need a bigger tank capacity air compressor if you want to work on bigger construction jobs than home upgrades.

How much space do I have?

There are larger capacity tanks that can only fit in a larger space. Therefore, if you have a smaller space, it will be a headache to incorporate. Most manufacturers try hard to integrate a compact design and portability. Otherwise, if you need a larger capacity tank but you have limited space, you can opt for vertical posture tanks rather than horizontal types.

Which tools will I use for the projects?

Air tools demand different air supply depending on the type and the tasks it performs. For instance, a brad nailer is a small tool that does not require much airflow so that a small capacity tank can run it effectively. On the other hand, some tools require a constant air supply, like a sandblaster. Therefore, you’ll have to go for a larger capacity tank that can provide more airflow without frequent stoppings during a refill.

What power source can I access easily?

A power source is needed to compress air into the air compressor tank. So, most units can easily be powered by an empirical home outlet, but some larger units require a 240v power source. Contrariwise, others can be powered by gasoline in case the electric outlet isn’t present.

Where will I be using it?

Yes, where to use your unit is a good question. Most of the time, after working in one station, you’ll be moving to the next site. Therefore, you’ll opt for a smaller-sized air compressor compact in design and lightweight for easy relocation. To limit fatigue and quickly move the tool to the next station will require comprehensive knowledge of the tank size.

The moment you incorporate all these questions in mind, I promise you’ll have a smooth walk in the park when answering the question, “how many gallons of air compressor do I need.”

Common Uses for Air Compressors

Air compressor is a versatile tool capable of performing multiple tasks. In the contemporary world, pneumatic tools have gained unmatched reliable power than electric counterparts. Moreover, air tools are less prone to wear and more resilient. The device works through a simple mechanism of compressing air in a tank and using it to drive air tools.

How many gallons of air compressor do I need

1. Tire Inflation

To fill a tire, you’ll need a 3-6 gallon tank delivering a range of 2-3 CFM. The size is also remarkable for portability. Here is our article on the best air compressor for a tire. Likewise, an air compressor of the same size is perfect for your home use or running small air tools.

2.Air Tools

The size of the air compressor perfect for air tools depends on the kind of work it performs. Smaller air tools run with a smaller CFM, which requires smaller capacity tanks, while heavy-duty air tools need high airflow from larger tanks. In general, a typical size of 8-10 gallons providing between 3-5 CFM can serve most tools. Let’s identify some air tools to discuss further.

3.Nail Gun

Nailing with a good nail gun requires faster and successive nail gunning, so you’ll need a 5-6 gallons tank supplying an airflow of approximately 5 CFM. Check out the best review and buying guide for brad nailers from our website. If you consider running two nail guns simultaneously, you must double the size of the tank. Moreover, a longer nail also requires more energy and power to drive.

4.Impact Wrench

An impact wrench is a powerful tool that demands a lot of air to operate. For a compelling performance, an impact wrench works best with a 6.0-gallon tank and a 5 CFM airflow. Check out to get the best impact wrench reviews and complete buying guide from our site.


Painting requires a frequent flow of air, so you’ll need a larger tank size. Anyway, the size also depends on what you are painting. For instance, painting a car requires a smaller capacity tank than painting a house.

6.Home Painting

In case you want to paint a house, consider getting a 5-6 CFM tank capacity. However, if you need to save time from refilling the tank, go for a larger tank like a 10-gallon tank and above.

7.Painting a Car

Despite being of less capacity than a house, painting a car still needs a constant air supply for uniform layers. The surface area requires a 6-8 gallons tank, but a larger tank will anticipate no pause for a refill.

8.Air Hammer

The air hammer demands a certain amount of pressure, generally between 90-100 PSI, depending on the model. Checking on the airflow, only 4 CFM is sufficient to run an air hammer.

9.Blowing Out a Sprinkler System

To blow out the whole zone at once, you’ll go for an 80 PSI air compressor running at an airflow of 10 CFM. However, confirm the maximum amount of pressure your polyethylene pipes can contain. On the other hand, to get the right CFM for a single sprinkler system, divide the gallons per minute (GPM) by 7.5. The results will give you the right CFM to blow that sprinkler head.

10.Sand Blaster

A sandblaster requires a higher airflow. If you have a four nozzle sandblaster, you will need an air compressor providing a pressure of 90 PSI and an airflow of at least 70 CFM. So high, right?

11.Hardwood Flooring

If you want to floor hardwood, you’ll go for a nail gun designed for hardwood only, and the size of the air compressor that can run it delivers around 4 CFM. This will ensure full-length driving of nails into the hardwood.

12.Garage Usage

A garage has many tools, and to get the right size of an air compressor, go for the one that can run all your air tools. One is an impact wrench, which will require 5 CFM airflow. Otherwise, plan for the most heavy-duty tool that you have. Here are our top picks of the best air compressor for the garage.

13.Air Grinder

A pneumatic angle grinder requires a 6-6.5 CFM airflow to run effectively. You should maintain the pressure at approximately 90 PSI. A die grinder will direct a lower pressure of 70 PSI and an airflow of 5 FCM.

Final Words

The air compressor size mostly dictates the airflow and pressure. However, it would be best if you also looked at other features as they dictate a lot regarding air compressor performance. For instance, the sound is a vital factor as you will know whether you need ear protection.

I’m happy you now know how many gallons of air compressors you need for any air tool you need. Remember to balance your air compressor size with the tool’s CFM since larger tanks are a burden in terms of movement and storage space. We hope the guide has been of great help.