3/8 vs. 1/2 Impact Wrench – Which One For You?

Impact wrenches for tightening the bolts, nuts, and screws or loosening don't only make your wood and metalworking projects easier but also save you a lot of time. And if you are a professional or you often do it, it is always a good idea to buy an impact wrench.

However, which size of impact wrench you should pick is still confusing among some people. The war of 3/8 vs. ½ impact wrench is still something that many woodworkers and metalworkers don't understand.

Today, we will make a small but detailed impact wrench comparison that can help you choose one for your job!

What is an Impact Wrench?

Before you get into the rivalry of 3/8 vs. ½ Impact Wrench, we must learn what impact wrench is and why we use them. An impact wrench is also popular as an impactor, impact gun, torque gun, and other names.

It provides you the ability to exercise a high level of torque. And you can do that with minimal effort. Here, we are dealing with the two different diameters of the impact wrench which are 3/8 and ½.

This is just like a standard wrench but with an automatic feature. You need a power tool to run this automatic wrench. It is used for tightening or loosening the bolts, screws, nuts, and other such objects.

Basic Difference between 3/8 and ½ Drivers

Here, we will learn about the basic differences between these two impact guns and decide which one to purchase.

Size and Weight

As we have discussed before, the number mentioned here is the diameter of the impact wrench. And so, the first difference we are going to talk about is the size of these impact wrenches. We need both of these impact wrenches for different work.

The first wrench is 3/8 and this one is the smaller one here. On the contrary, the ½ driver is the larger one on the list. Apart from the size, the weight is also different between these two impactors. The first one which is smaller in size has a lightweight body.

On the other end, the ½ driver is the one that heavier than the first one. In that case, working with the larger one is tougher but when it comes to maneuvering the smaller one, it is easier to deal with it!


Just as the size differs, the functionality of these two impact wrenches also differs at some points. Yes, both are designed for doing the same work but there are necessary differences between them too.

When you are dealing with the small 3/8 impact wrench, you can easily go through the tight spots and tighten them with precision. On the contrary, it will be tough for a ½ impact wrench to get inside a tight spot and then tighten it. You will not be able to reach the exact spot in some cases.

On the other side, if you often need to work with bolts of 10mm or less, we recommend you purchase a 3/8 impact wrench. It is the best size for such functions. Along with this, this size is ideal for all the delicate and precise work that you need!

Power and Popularity

The large driver here is the ½ impact wrench. This wrench is popular and more common among users. In some cases, power and precision are what you need. And in such situations, you will prefer the ½ impact wrench more than the 3/8 small impact wrench.

When it comes to the position, the large wrench will fit squarely in the center of the spectrum of your driver sizes. And a result, an ideal balance of precision and power is created there. Whenever you plan to remove the nuts, bolts, and screws, the safest option to go for is the ½ wrench.

We call it a safe option because when you remove the nuts and bolt with this impact wrench because it is easy to work with it without any potential damage. As you do not need to apply too much force, you can avoid potential damage.

When it comes to the power options, you must learn that some of these wrenches are corded and others are cordless. Check out the Corded Electric Impact Wrench for the best wrenches that require direct electricity.

And if you want a battery-operated one, Automotive Cordless Impact Wrench can present you with an ideal wrench for your job. In short, if you are talking about power and popularity, we always suggest you get the ½ impact wrench. For any heavy-duty projects, you can simply get your hands on the ½ wrench over 3/8 impact wrench.

Torque Strength

When you plan to settle for the ½ impact wrench, you should know that it puts out torque strength from 20 pound-foot to 150 pound-foot yield, which is massive! So, for all the rigorous and tough work, where you need a lot of torque, you can rely on the ½ wrench without any confusion.

If you compare the 3/8 regarding the power and torque, yes, this lacks the power you need for heavy-duty jobs. The torque strength of the 3/8 impact wrench is about 10 pound-foot to 90 pound-foot yield.

So, whenever it is a heavy job, go for the larger one. And if you have smaller jobs that require precision, the smaller one is the best bet ever.

Material Selection

The ½ impact wrench has balanced strength; you can pick it up for hefty jobs where the materials can handle a lot of torque and power. If you use this one on a material that is vulnerable and fragile, the use of the ½ wrench can damage the material with its high torque and power.

The bits that you use should complement the material of your workpiece. For more detailed info, go through Impact Driver Bits Sets and pick up one that fits your desired material.

For all the small jobs and DIYs, you can gladly pick up the 3/8 impact wrench because these are designed for such jobs. The smaller wrench will provide you limited power for the materials that are fragile and will tighten or loosen the bolts and screws carefully.

You can pick up this one for your woodworking purpose. Such wrenches will never disappoint you when it comes to smaller and précised jobs with feeble materials.

Comparison Chart

We have selected the two best impact wrenches by two different brands in 3/8 and ½ sizes. The Bosch GDX18V-1800CB15 Freak ½-inch Brushless Impact Wrench and the Milwaukee 2767-20 M18 Fuel 3/8 ”“Inch are loved by the users and you can try them too!

Size (inches)3/8 inches½ inches
PowerBattery PoweredBattery Powered
Torque2520 Inch Pounds1800 Inch Pounds
Power SourceCordlessCordless
Duality Only WrenchDriver+ Wrench
LEDTri-Beam LEDSingle LED
Speeds3 Speeds1 Speed
Modes4 Modes1 Mode

Wrap Up

Once you find yourself in the conflict of 3/8 and ½ impact wrenches, you can read out the differences and know which one is the best to buy.

If you are interested in woodwork, metalwork, and DIY, check out our blog to learn more about them and inspire yourself!

About Jeremy

Hello! My name is Jeremy Bloomberg. I have been passionate about carpentry and DIY. Over the years, my passion slowly turned into expertise and wider knowledge about electronics. I’ve been involved in numerous projects, both professional and personal. I want to share all I have learned with you. Welcome!

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