Best Cordless Impact Wrench for 2022

An impact wrench is a battery power tool designed to loosen and tighten nuts and bolts just like a manual socket wrench, but since it has a power source greater than just your arm, it can provide far more torque (it also needs special sockets given the amount of torque at play). The most common automotive applications for impact wrenches are loosening and tightening lug nuts for the purpose of changing tires.

While pneumatic air impact wrench models have been the standard in the past, they require connection to air compressors, meaning that they're not accessible for all DIYers. "Cordless tools are lighter weight than air tools, which makes them more portable for use overhead or in tight spaces," says John Linden, lead designer at MirrorCoop. Linden has years of both construction and design experience. "These are considered 'good' as they don't need any extra equipment (like a compressor) to run."

"Cordless impact wrenches have made great strides in the past decade in terms of increasing performance and decreasing size," explains Joshua Tarini. Tarini is group product manager -- impact wrenches and specialty fastening at Stanley Black & Decker. "Benefits of cordless/electric options are freedom from hoses, not being dependent on an air supply and, in general, less maintenance than when using an air tool. Many professional automotive mechanics have made the switch to cordless as their primary tool platform and away from pneumatic."

Today, cordless battery electric models are more popular, especially for home use. They just need to be charged and they're ready to go. While corded electric impact wrench options are available, as well, the cordless ones are favored for their portability. The tradeoff is that they typically provide less power than the other two types of impact wrenches (but still a sufficient amount for most home garage applications).

Like regular socket wrenches, battery impact wrenches provide the twisting force known as torque, just in greater amounts. The user holds the impact wrench steady, but the end of the tool, which grips the nut, bolt, or screw that needs to be loosened, spins in short, fast bursts. Like other cordless tools, they're powered by internal batteries that can be recharged, though all batteries eventually experience permanent drainage.

Finally, it's important to note that battery impact wrenches and impact drivers are two separate tools and the terms should not be used interchangeably. An impact driver is used for driving screws and bolts with similar bursts of power to those of an impact wrench, but it's more comparable to a power drill or screwdriver (just with more torque).

Cordless impact wrenches are powered by batteries, but apart from that, they vary in many ways. The two main shape categories into which they fall are inline (shaped more like a screwdriver) and pistol-grip (shaped like a handgun). Pistol-grip wrenches are typically bulkier, but the design also allows for larger socket sizes -- at ½-inch or above, you'll likely be using a piston-grip wrench.

Another variation comes in the power delivered by the batteries. Like all electric tools, their power is measured in voltage. Most impact wrench batteries are either 18 or 20 volts, with the 20-volt models usually considered preferable since they provide more power, though factors like motor type also influence power.

"Generally speaking, 20-volt is better than 18-volt," says Tim Koster, founder of Clever Creations. Clever Creations is a website dedicated to DIY projects, repair guides and tool reviews. "The higher the voltage, the more power the tool has. That said, a specific 18-volt model impact wrench can still be stronger than a different model that works on 20-volt. Voltage is not the only thing to consider."

Another important consideration when choosing a cordless impact wrench is torque. Torque, the twisting force that gives impact wrenches their abilities, is measured in pound-feet, which is determined by multiplying the force acting on an object (in pounds) by the distance of the lever being used to exert the force (in feet). While an impact wrench doesn't use an actual lever, pound-feet can still be used as a universal scale by which to measure torque. However, the abbreviation is often written in reverse, as "ft-lb."

Torque varies based on impact wrench size, with 1/2-inch impact wrenches providing an average of 300 pound-feet of torque and 3/4-inch impact wrenches providing an average of 1,200 pound-feet. An impact wrench's torque can't be adjusted by itself, but there are attachments that can vary the torque. Additionally, torque shouldn't be confused with inches per minute (IPM) or revolutions per minute (RPM). While there is a mathematical relationship between the measurements, IPM and RPM measure speed, not torque.

Of course, the amount of torque you need depends on your application, as well: "If you do a lot of automotive work, then you can benefit from up to 500 pound-feet of torque," says Koster. "If you only do light work, on the other hand, 200-250 pound-feet will be more than enough."

There are other features that differ between battery impact wrenches, as well. For instance, some have variable-speed triggers, which means that the speed at which the wrench turns is controlled by how hard the user presses the trigger. Impact wrenches also differ based on how their sockets are secured, with ball or pin detents providing more security and friction (or hog) rings providing easier release.

"A friction ring is typically preferred, especially when swapping out sockets a lot," says Koster. "Detent pins are notoriously difficult to work with." That said, if you won't be changing sockets, you may prefer the tight grip of a pin detent.

"Each anvil style has its own benefits," says Tarini. "For users who need maximum socket retention and are generally not changing sockets frequently -- such as those working at height where a dropped socket might be hazardous -- the detent pin design would be preferred. For users who are switching socket sizes more often, the friction ring design allows for strong socket retention while allowing an easier socket change. In the case of the automotive user, the friction ring is the preferred design as it provides the socket retention needed while allowing the user to quickly change sockets without additional tools (which may be required on some detent pin designs)."