I have been working with power tools for over 30 years and often get asked the question “Impact Driver vs Impact Wrench – what’s the difference?”. 

I remember the introduction of Impact Drivers and Impact Wrenches to the industry. I have given this answer countless times and have detailed the key differences.

Most guides go into lots of technical jargon on the differences between Impact Drivers and Impact Wrenches. Others only focus on the difference in use. I have focused on both of these points. I discuss the main difference in uses of these tools then describe each tool in detail.

10 second summary of differences 

Simply put – an Impact Driver is a screwdriving specialist whereas an Impact Wrench is used for fastening and loosening nuts and bolts.

An Impact Driver is used for many screwdriving tasks. It has a head that requires a driver bit to install and works with a variety of fasteners. 

An Impact Wrench is much higher powered and has more torque than a power drill. Because of this, it is not a ‘general screwdriving power tool’. 

What is an Impact Driver? (And what is the difference between an Impact Driver and a Drill) 

An Impact Driver looks like a cordless drill and looks almost identical to an Impact Wrench. 

The Impact Driver delivers very high torque (rotational force). The Impact Driver delivers both high rotational force and an ‘impact’ in a radial sense. This is a rotational hammering force – imagine hammering round a screw. An internal hammer attached to the motor strikes the anvil which is attached to the bit. 

Note: Impact Drivers are not hammer drills. On a hammer drill the bit moves in and out, whereas on an Impact Drive the bit stays put. The hammering action takes place inside the tool. 

This mechanism produces huge amounts of torque with use of the ‘hammer blows’. Impact Drivers produce around 170 Nm. Due to the high rotational speed the machine excels at drilling very fast. It is capable of drilling long screws into hard material. 

Pros

• Provides a huge amount of torque. Tightening or removing very tight screws is easy. 
• ‘Reactive torque’ is reduced. This means your arm is less likely to experience a kick back by the machine. 
• More comfortable to use for long periods of time. 

Cons

• Very heavy wear and tear on standard screwdriver bits. It’s recommended to use specialist impact resistant bits which are more expensive. 
• No torque control or gears. When more torque is required the impact mechanism is activated. 
• Screws can be damaged and threads chewed due to the high power. Here’s a guide on how to remove a stripped screw. 

Impact Driver vs Drill

An Impact Driver looks like a regular power drill but delivers more power. An Impact Driver is tough enough to drill through wood, metal and bricks due to it’s very high torque. A power drill is multi-purpose and is good for most DIY projects. Here’s a guide on the most essential tools for DIY.

A power drill is an adjustable speed tool capable of drilling and driving fasteners. The drill’s head has a keyed or keyless chuck that holds bits securely in place. Most drills fit standard bits and hex bits. Here’s a guide on different drill bits and their uses. 

The Impact Driver does not have a chuck. Instead they have a clamp that holds drill bits and driver bits with a hexagonal shank. 

The power drill is less powerful but features adjustable power. This means it’s a more general purpose tool suited towards a variety of tasks. The Impact Driver is a drilling specialist and is more comfortable for use over a long period of time. 

Here’s a video on how to use an Impact Driver: 

What is an Impact Wrench? 

An Impact Wrench looks like an Impact Driver but may be larger. It is also a high-torque tool. 

The main purpose of an Impact Wrench is to fasten or loosen nuts and bolts. Impact Wrenches provide a powerful alternative to the traditional ratchet and spanner. 

With a standard wrench you would attach the wrench to the bolt then hit the wrench with a hammer to apply percussive torque in order to loosen the bolt. An Impact Wrench does this. 

Impact Wrenches are commonly used in car and gardening machine maintenance. 

The Impact Wrench has far more torque compared to an Impact Driver. The torque ranges from 300 to 2200 Nm. This is a large range because the Wrench is a more specialised tool compared to the Impact Driver and has a larger variance of performance. 

Because of the specialist nature of the Impact Wrench we’re not going to do pros and cons. The only real alternative is to use a ratchet or spanner. 

Here’s a video on an Impact Wrench working in slow motion: 

5 fundamental differences 

The uses of Impact Drivers vs Impact Wrenches are very different. Drivers are for driving screws whereas wrenches are for tightening and loosening nuts and bolts. There are some more specific differences related to the machines themselves. 

Drive Styles

Impact Drivers use a ¼ inch hex accepting ¼ inch hex shank bits. Impact Wrenches use a square drive where a socket can be attached. 

Impact Drivers only come in a few different styles but all have a ¼ hex collet. Impact Wrenches are more specialised and as the power increases, so does the hex size. The smallest wrenches will be a ¼ inch drive whereas the largest is at 1 inch. 

Power Sources

Most Impact Drivers are cordless and powered by battery. They are usually powered by 12v, 18v and 20v. 

Impact Wrenches come in both corded and cordless versions. The classic Impact Wrench is powered by compressed air. These machines require an Air Compressor. Click here to learn how to choose an Air Compressor. Mechanics would use pneumatic Wrenches whereas trades guys would use cordless. 

Torque 

The Impact Wrench has far more torque than an Impact Driver. More torque is required to tighten a bolt compared to driving a screw into a wall. 

Speed

Most Impact Drivers deliver faster speeds compared to Impact Wrenches. 

Impact Driver: Roughly 3600 RPM

Impact Wrench: Under 2000 RPM. 

Note: A pneumatic wrench delivers much faster speeds at around 8000RPM. 

Size

Impact Drivers are smaller than Impact Wrenches. There is less variance with the size of Impact Drivers. 

Impact Wrenches can vary greatly in size linked to the amount of torque produced. 

Note: Pneumatic Wrenches can be far lighter as there are fewer moving parts. 

Next steps 

I hope you’ve enjoyed this comprehensive guide on the differences between an Impact Driver and an Impact Wrench. 

If you’d like to know more about any kind of hand or power tool, please comment your ideas below.