Best Air Compressors for Impact Wrench – What Size Do You Need?

Last night I was poking around the internet and noticed something shocking. Someone was recommending a pancake air compressor with a CFM rating lower than 2.0 for an impact wrench!


Even a 3/8” impact wrench requires at least 2.5 CFM at 90 Psi, how can someone give such terrible advice.

For impact wrenches, the CFM rating is more important than the pressure rating and tank size of the air compressor. Impact wrenches are air gannets. If you don’t supply enough air, it won’t work at all.

If you are looking for the best air compressors for impact wrenches, then I have some special recommendations for you.

Makita MAC5200 Big Bore 3.0 HP  (Link to Amazon)  is the best air compressor for 3/8″ and 1/2″ impact wrenches. It is rated with 6.5 CFM at 90 PSI. Powermate Vx PLA4708065 (Link to Amazon)  is the best air compressor for 3/4″ and 1″ impact wrenches. It is rated with 14.0 CFM at 90 PSI.

Although there are other alternatives to these air compressors, these two are more reliable and performance is proven.

You may ask why?

I will show you the reasons behind that. So stick with me to the end.

What Size Air Compressor Do You Need for Impact Wrench?

As I have said earlier, the CFM rating is the most important factor that you should consider before buying an air compressor for your impact wrench. The larger and powerful your impact wrench is, the more CFM it will require.

Impact Wrench Size and Normal CFM Requirement

The most common size of impact wrenches is 3/8″, ½”/, ¾”, and 1”. CFM requirement goes up as the size increases.

The minimum size of air compressor for impact wrenches are given below –

For 3/8” Impact Wrench: 2.5-3.5 CFM at 90 Psi

For 1/2” Impact Wrench: 4.0-5.0 CFM at 90 Psi

For 1” Impact Wrench: 7.0 CFM at 90 Psi

For 1” Impact Wrench: 10.0 CFM at 90 Psi

CFM Requirement Increases as Impact Wrench RPM Increase

Apart from the size, the CFM requirement also depends on the RPM of the Impact wrench. For more RPM, you will need more CFM.

For example, the DEWALT DWMT70773L 1/2-Inch Square Drive Impact Wrench has 7500 RPM and it requires 5.9 CFM at 90 PSI while the AIRCAT 1150 1/2-Inch Impact Wrench comes with 9000 RPM and requires 8.0 CFM at 90 PSI.

So don’t blindly depend on the size of your impact wrench, rather know what CFM it is asking for.

You Need More CFM than the Actual CFM Rating of Your Impact Wrench

The efficiency of any machine decreases as it gets older.

Say, for example, you buy an air compressor with a 3.6 CFM rating, and your impact wrench also calls for a 3.6 CFM rating. In that compressor will work well for one or two months.

But as it gets older, it will lose some of its efficiency and will not give the same performance as that 3.6 CFM rating Impact Wrench.

Therefore, it is recommended that you buy an air compressor that has 1.25 times more CFM than your Impact wrench. The same goes for all other air tolls.

Best Air Compressor for 3/8” and 1/2” Impact Wrench

For 3/8” and ½” impact wrench, my first recommendation is the Makita MAC5200 Big Bore 3.0 HP Air compressor which comes with a 6.5 CFM rating at 90 PSI. Although there are other Quiet and Portable Compressor available, this one from Makita is more reliable than them. I will talk about them later in this article.

Makita MAC5200 Review – Why it is My First Choice

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The Makita MAC5200 is my favorite for its versatile application, compact design, mobility, and durability. This one is the most suitable air compressor for garages and workshops use. It is built for professionals who need both power and performance.

As you are looking for an air compressor for an impact wrench, you should keep the CFM as the first priority. I have said it earlier that this compressor comes with a 6.5 CFM rating. Therefore, this compressor has enough CFM to power a ½” impact wrench and it is more than enough for a 3/8” one.

The MAC5200 features a 3.0 HP 3420RPM motor that is rated with13.8 amps. It is a 4-pole induction motor and Makita has used thick copper wire for this motor while others use thin copper wire to save build cost. Therefore, this motor gives the outmost powerful performance.

This air compressor features an automatic pressure switch. This switch can turn off the compressor when it is full at the pressure you adjusted and turn on when the pressure is lower.

As the name suggests, the pump of this compressor is featured with a big bore cylinder-piston. The advantage of the big-bore cylinder pump is, it takes half of the strokes of a narrow one. As a result, this compressor can fill its 5.2-gallon tank at 140 PSI in just 2 minutes.

The pump of this compressor is oil lubricated. There are both advantages and disadvantages of an oil-lubricated pump.

There will be less friction and hence wearing and tearing in the pump due to the lubrication. As a result, the pump lasts longer. It has an oil sight glass through which you can check the oil level. A sight glass is better than a dipstick as it doesn’t require opening it.

But it also requires checking and change the oil on a regular basis for good performance and unwanted problems.

The tank size of this compressor is 5.2-gallon. It is not huge but enough to lose and tighten bolts and lug nuts. There are two 1/4″ air hoses that let you connect and use two air tools at a time.

It also features a high-grade air filter. This filter keeps the dust away and supplies clean air for your tools. Drain valve is necessary for air compressors to drain out water from the air tank and it has one at the bottom.

Two pressure gauges are integrated on the metal-built control panel to monitor output pressure and tank pressure.

As you know the compressed air that comes out of the pump is hot. To cool it down, Makita installed a finned tube alloy fin while most of the other manufacturers use a normal tube for this job. Having a finned tube transfers the heat quickly and efficiently and supplies relatively cool air for your air tools.

Talking about portability, this compressor comes with a compact design, two 8” pneumatic wheels, and a foldable handle for easy maneuver. These make it the best portable air compressor for impact wrench.

Due to the pneumatic wheels, it also creates less vibration while running. For storing your small tools it also features one small storage facility.

The Makita MAC5200 do has some downsides also. It is louder than an average air compressor. While running at full power, it creates 90 decibels of noise. It won’t be a problem if you are used to working with power tools. But if you aren’t comfortable with such noise, then you can consider buying a quitter one the California Air Tools 10020C that creates only 70 decibels of noise and gives almost the same performance.

California Air Tools 10020C

This is an oil-less ultra-quiet 2 hp air compressor that has a CFM rating of 5.3 at 90 PSI and creates only 70 decibels noise while running. It has two wheels. Therefore good for maneuver.

California Air Tools CAT-4620AC

It is a 4-gallon twin tank air compressor rated with a 5.3 CFM rating and features a 2.0 HP motor. Like the 10020C it also creates only 70 decibels of noise and oil-less. There is no wheel attached to this compressor. Therefore, you may find it hard to move.


If you are a fan of Dewalt tools you can also consider buying this 4.5-gallon oil-less air compressor. It has a 5.0 SCFM rating and creates 78 decibels of noise. It runs with a 1.6 HP motor. Therefore, it consumes less electricity. It also has two pneumatic wheels for easy maneuver.

Best Air Compressor for 3/4” and 1” Impact Wrench

My recommended air compressors for heavy-duty impact wrenches are the Powermate Vx PLA4708065 and the 2340L514 two-stage air compressor from Ingersoll Rand. I will show you the reasons behind such a recommendation.

Powermate Vx PLA4708065 – Why I Recommend This

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The Powermate Vx PLA4708065 is designed to work with a wide range of air tools and comes with a 14.0 CFM rating. Hence it is capable of powering both ¾” and 1” impact wrench.

This single-stage air compressor features a 3 cylinder oil-lubricated pump. Because of the three-cylinder, it can produce huge output. The oil lubrication prevents wearing and tearing in the pump. It also helps to keep the pump temperature low. Hence the pump lasts longer than an oil-less pump. But you have to change the oil regularly. There is a sight glass for checking the oil level and accessing the oil changing facility is very easy for this compressor.

The Powermate Vx PLA4708065 runs with a 4.7 HP 240 volt heavy-duty induction motor. 14 CFM at 90 PSI from 4.7 HP proves the efficiency of the whole system.

Wire-formed belt guard cools the hot air efficiently and also gives protection from the moving parts, wheel and belt.

This compressor comes with a huge tank capacity of 80-Gallon. This much tank capacity is capable of taking the heavy workload.

But due to the large tank size, this one weighs about 354-lbs. Therefore, you have to keep this air compressor in a fixed position and it requires at least 3 adult persons to move it.

The noise level of this compressor is 83 decibels. This is lower than most of the other single-stage air compressors and a single-stage air compressor creates more noise than the two-stage air compressor.

This one comes filled with synthetic oil but no water filter and pressure regulator. Powermate recommends professional installation for this air compressor.

In my opinion, this one is dependable for wrenching and other heavy-duty air tools.

Although the Powermate Vx PLA4708065 is a good fit for most of the 3/4″ and 1″ impact wrenches, sometimes you may require more power and CFM to run an impact wrench If it has a higher free RPM. In such a case, you can consider the following air compressor.

Ingersoll Rand 2340L5

It is a 60-gallon air industrial performance air compressor that comes with 18.1 CFM at 90 psi and 175 PSI maximum pressure. With this much CFM, you can power a 1” wrench.

It features a 5 HP motor and durable two-stage pump that gives a long-lasting service of 15,000 hours. The pump is oil lubed and using all-season select, it requires a change out every 2000 hours. This is longer than any other compressor and a good advantage. Being a two-stage compressor, it also creates less noise.

Ingersoll Rand 2340L5 is more powerful than the Powermate Vx PLA4708065 and comes with a little bit higher price point. Therefore, I will only recommend this one if you are a garage geek or professional.

Questions You May Ask

How many gallon air compressors for impact wrench do you need?

The tank size of the air compressor doesn’t matter much when you use it for impact wrench. The thing that matters most is the CFM rating of the air compressor. The more CFM an air compressor has, the powerful the impact wrench it can run.

But still, it is recommended that you have at least a 4.0-gallon tank capacity for impact wrench.

What kind of air compressor do you need for an impact wrench?

An impact wrench generally requires from mid-range to high-end air compressor according to its size variation. The best practice is to use an oil-lubricated single-stage or two-stage air compressor. Again you should always avoid a pancake compressor for impact wrench. Most of them don’t work with an impact wrench, some do, but not well. They are only good for a nail gun.

The Smallest air compressor that can run an impact wrench

The smallest air compressor for an impact wrench that I suggest is the Makita MAC700 (See at Amazon). It is rated with 3.3 CFM at 90 PSI. Therefore, can easily power a 3/8” impact wrench.

It is featured with a 2.6-gallon tank and is very compact and lightweight.

Will a 2.6 SCFM compressor work for an 8 CFM air impact wrench?

1 SCFM is equal to 1.2 CFM. Therefore, 2.6 SCFM is equal to 3.12 CFM. So, a 2.6 CFM air compressor will not work for an 8 CFM air impact wrench due to a lack of 4.88 CFM.

However, you can try to increase the CFM of your air compressor and it may work.

So, you can see the CFM rating of an air compressor play the greatest role when you use it for impact wrench. Therefore, before you buy an air compressor for an impact wrench, check the CFM of your wrench. Make sure your compressor can supply enough air for your impact wrench.


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