What is The Difference Between PSI and CFM?

What is the difference between PSI and CFM? PSI and CFM are both essential for an air compressor. To understand the air tool’s performance, you must know the PSI and CFM.

PSI represents the air pressure of an air tool. Conversely, CFM represents the volume of compressed air per minute that an air tool can supply. Both are related to providing the best performance of air tools. 

You are going to the market to buy an air compressor. But you can not understand PSI and CFM. Before purchasing a compressor, you have to understand PSI and CFM. We will discuss all the terms of them. Also, examine the difference between PSI and CFM.  

What is PSI?

The complete form of PSI is pounds per inch. It is a unit for measuring air or water pressure. The PSI measures single square air pressure. To get a perfect air compressor, you need to know the PSI. All the air tools are not required the exact PSI. 

For example, an air compressor PSI is 70. That means the air compressor can create 70 pounds of force per square inch area. 

What is PSI Pressure

What is CFM

The acronym of CFM is cubic feet per minute. It measures the volume of compressed air. The CFM represents how much compressed air supply in one minute.

For example, an air tool CFM is 4. That means the air tool can produce four cubic feet of compressed air per minute during work.

How Much PSI is Best for You?

Generally, the compressor manual book mentions the PSI rate. You can check the PSI rate from the manual book according to your work. If you don’t find it, you can determine PSI for your tool. 

The PSI rating depends on some factors.

  • What type of work do you do and
  • what kind of tools do you use

These two factors are essential for determining the PSI rating. 

Most air tools require between 70 to 90 PSI. But you should find the specific rate according to your device and task.  

Don’t go to a high-range PSI compressor if you need little range PSI because an excess PSI rating can damage your air tool or face trouble in your work.

Some air tools are manufactured with over 150 PSI. That is enough for all types of work, including home and garage. However, you can select a low PSI rating if you want to use an air tool for home or small jobs. It would help if you had a high-range PSI air tool for garage work or heavy work. Also, you must check the air tool type. 

Care Your Air Tool PSI

Every air tool is designed with a specific PSI rate for operation. The air tool cannot work correctly if you are not fulfilling the required PSI. Also, the device will damage if you provide less PSI or too much PSI. That’s why you should always offer their specific PSI according to their requirement. 

An air compressor can produce 150 PSI. That does not mean you can provide too many tools. You must regulate PSI rating according to your devices and adjust your work. Also, check other factors of your tool before operating.    

How Much CFM is Best for You?

Like PSI, every air tool is designed to operate with a specific CFM. You have to match the CFM rating with your work and air tool. The air compressor cannot perform well if you can’t adjust the CFM rating with your devices and labor. So you must select an air tool with enough CFM to operate your tool perfectly.

All air tools are not required the same CFM rating. Also, you need a specific CFM according to our work. You can find out the required CFM easily.     

  • First, find out how much CFM requires your tool
  • Then, multiply 1.5 by the required CFM 

Care Your Air Tool CFM

Selecting CFM ratings for air compressors is more complex than PSI. Because the CFM rating change vehemently. On the other hand, most compressor PSI rate is 150 to 175. That is enough for every type of home or garage work. Also, they can produce enough pressure for all the tools and perform properly.  

You are wrong if you think any CFM rate can adjust with this high PSI rate. Before buying a compressor, you must find the right CFM rating. If you can not match the CFM rating or use any CFM rate, your tools become damaged. You also can not operate perfectly.  

So, meeting the required CFM rating with your air tool and work type is essential.   

The difference Between PSI and CFM

CFM or cubic feet per minute is the ability to perform a certain over time. CFM requires airflow. CFM expresses how much time need an air tool to finish a task. Also, we can know the amount of airflow from the CFM rating.  

You need to know how much time you spend completing a work. You can do a work plan. So, a CFM rating is essential for choosing an air compressor. The compressor requires a break to rebuild pressure in the reserve tank.    

PSI or pounds per square inch requires pressure. Like CFM, PSI is also important to determine the compressor size. The PSI rating discloses the amount of pressure of a compressor. You can know how much pressure you need for a specific work from the PSI rating. The air tool must provide the proper pressure to finish a task. 

PSI and CFM are both critical factors for a compressor. A compressor can work for pressure and airflow. In the compressed term:

  • Horsepower delivers flow
  • Pressure delivers the force 

The compressor needs the required pressure and airflow. Too much or too little pressure damages the tool and can not provide good performance. At this point, you can work properly. So you have to find your tool’s specific PSI and CFM. 

The CFM and PSI help an air compressor meet the required operating tools. Every air tool requires a perfect CFM and PSI rating to work correctly. So you have to be careful when you calculate these two ratings. Consider the following factors for calculating the CFM and PSI rating. 

  • Calculating the requirement for each of the tools that you want to use 
  • How long do you operate the tool   
  • How much does your equipment run at the same time  

PSI and CFM 

Let’s see at a glance the difference between PSI and CFM. 

The acronym of PSI is Pounds Per Square Inch The acronym of CFM is Cubic Feet Per Minute 
Requires the amount of pressureRequires the amount of airflow
Unit of air or water measure pressureUnite the measure of airflow
Measures single square air pressureMeasures how much-compressed air supply in one minute
Most ait tool requires 70 to 90 PSIMost air tools require 0 to 5 CFM

Chart of PSI and CFM According to The Air Tool

There have several types of air tools for different types of work. The functions and features are other in all the air tools. So the ratings of PSI and CFM are different for various air tools. 

When buying an air tool, you must check the PSI and CFM rating. Also, know the required rating of your air tool. Here, we will give a PSI and CFM chart for different air tools. 

Air ToolPSICFM (minimum require)Requirement CFM
Roofing Nailer70-120 PSI3.7 CFM2.5 CFM
Brad Nailer60-90 PSI1.5 CFM1.5 CFM
Framing Nailer90 PSI3.7 CFM2.5 CFM
⅜ Air Drill90 PSI10.2 CFM6.8 CFM
⅜ Ratchet90 PSI6.6 CFM4.4 CFM
¼ Ratchet90 PSI6.3 CFM4.2 CFM
¼ Angle Die Grinder90 PSI6.7 CFM4.5 CFM
½ Impact Wrench90 PSI7.5 CFM5 CFM
Air Hummer90 PSI6.6 CFM4.4 CFM
HVLP Paint Spray Gun30 PSI12 CFM8 CFM
6-inch Palm Sander90 PSI6.7 CFM4.5 CFM
3 inches Cut Off Tool90 PSI6.7 CFM4.5 CFM

What Size Air Compressor is Good for You

We already discussed the PSI and CFM and gave the chart of PSI and CFM according to the air tool. We hope you find out what size air compressor is good for you.

Air compressor size depends on several factors. The PSI and CFM are most important from them. For choosing an air compressor, you must find your task type and what tools you use. 

You get a good air compressor performance if you match the compressor requirement. What type of air tool do you use? That also essential to know the compressor size.  

Final Thought

What is the difference between PSI and CFM? We discussed this topic in this article. So, now you can understand the PSI and CFM. The PSI measures pressure and CFM measures airflow. Both are important factors in choosing a suitable air compressor.

Most air tools require 70 to 90 PSI and 0 to 5 CFM. You have to calculate PSI and CFM according to your device and work. The compressor manual book can find the PSI and CFM rates. By any chance, the manual book dose does not mention the speed; you can determine the rate.

You just determine factors like the requirement of each tool you use, your operating time, etc. We already discussed all of it. Just remember, you have to meet all the requirements of your air compressor. If you can not fulfill the need, the compressor becomes damaged. Also, the compressor provides terrible performance.           


Is PSI is same as CFM?

No, PSI is not the same as CFM. PSI or pounds per square inch, measure air or water pressure. CFM or cubic feet per minute measures airflow or volume.    

What is the CFM at 90 PSI?

Generally, the CFM rating is given a specific PSI rating. You have to use that particular CFM rating. It would help if you operated an air compressor properly. 

Does lower PSI mean higher CFM?

Manufacturers always give a specific PSI and CFM rating for each compressor. You have to use the required rate. Lower PSI means not higher CFM. It depends on your equipment and work.    

What is a good PSI for an air compressor?

Most compressor comes with 70 to 90 PSI. With this PSI rate, you can operate the compressor for any light to medium duty. It is perfect for any homework.

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