Wrench Guide: Types of Wrenches, Uses and Features

Choosing the right wrench for a project involves more than just matching sizes. Use the right style of a wrench to make your project easier.

Wrenches perform the same function as ratchets and sockets, tightening and loosening fasteners, but there are differences and situations that call for one over the other. For example, a box-end wrench is a good option for loosening stuck fasteners because you can apply more torque without risking damage to a ratchet mechanism.

A wrench with an open-end fit around a fastener instead of over it, so you can slip it into an area where there isn’t room for a socket. Always make sure the tool you use is suited for the work you’re doing.

Types of Wrenches

Wrenches are available in a variety of styles for different applications. Some are designed to work with standard (Society of Automotive Engineers or SAE) fasteners, and some are for metric applications.

  • Adjustable Wrench
  • Combination Wrench
  • Open-End Wrench
  • Ratchet Wrench
  • Short-Body or Stubby Wrench
  • Crowfoot Wrench
  • Basin Wrench
  • Pipe Wrench
  • Hex Key/Allen Wrench
  • Star-Head Key/Torx Key
  • Strap Wrench
  • Chain wrench
  • Socket wrench
  • Torque wrench
  • Oil Filter Wrench
  • Impact Wrench
  • Pedal Wrench
  • Monkey wrench
  • Pliers Wrench
  • Plumber’s Wrench
  • Tap Wrench
  • Spud Wrench
  • Alligator Wrench
  • Basin Wrench
  • Armorer’s Wrench
  • Dog Bone Wrench
  • Drum Key
  • Bung Wrench
  • Fan Clutch Wrench
  • Hammer Wrench
  • Cone Wrench
  • Tension Wrench
  • Spoke Wrench
types of wrenches

1. Adjustable Wrench

An adjustable spanner or adjustable wrench is an open-end wrench with a movable jaw, allowing it to be used with different sizes of fastener head (nut, bolt, etc.) rather than just one fastener size, as with a conventional fixed spanner.

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More commonly referred to as a crescent wrench, these are one of the most popular wrenches available. They have an open end with a spiral screw embedded that opens or closes the crescent as you turn it.

For this reason, it can perform the same basic function as an entire set of combination or open-ended wrenches, although it requires more space due to its thicker size.

  • Tightens/loosens nuts and bolts
  • Moveable lower jaw to adjust wrench size
  • Works with both standard and metric fasteners

2. Combination Wrench

If box-ended wrenches and open-ended wrenches had children, the combination wrench would be the result. One side is a closed-loop for hexagonal or square nuts, while the other end is an open U-shape.

Used most often for difficult nuts, the closed-end loosens the nut so that the open end can be used to quickly unscrew it. Like sockets, combination wrenches are usually sold in sets containing a variety of wrench sizes.

  • Tightens/loosens nuts and bolts
  • Metric and standard sizes
  • One open end and one box end (usually the same size)
Types of Wrench

3. Open-End Wrench

One of the most common types of wrenches found in toolboxes, the open-ended wrench has two U-shaped ends, with one being slightly bigger than the other. They are used for hard-to-reach nuts and bolts, and the open design makes it possible to attach them either vertically or horizontally onto the target fitting.

The downside is that they are more likely to round the edges of a nut than box-ended wrenches.

  • Tightens/loosens nuts and bolts
  • Metric and standard sizes
  • Two open ends (usually different sizes)
  • Jointed or flex-head models let you work at different angles

4. Ratchet Wrench

Similar to open-ended wrenches, box-ended wrenches, and combination wrenches, ratcheting wrenches have at least one end that has a ratcheting device inside of it.

This allows you to turn the wrench to tighten or untighten without having to remove and readjust the position if the wrench handle hits an obstacle after each turn. It makes working in tight areas a lot easier.

  • Tightens/loosens nuts and bolts
  • Metric and standard sizes
  • Ratchet action on one end moves freely in one direction and engages the fastener in the other direction to tighten or loosen nuts and bolts without removing the tool
  • Some have pivoting ratchet ends for use in tight spaces

5. Short-Body or Stubby Wrench

Referred to as a short body wrench in polite circles, this is a shorter version of a combination wrench, allowing it to fit into more confined spaces.

Some newer versions also have a hinge along the handle to allow either end to be angled for even more precise use.

  • Tightens/loosens nuts and bolts in tight spaces
  • Metric and standard sizes

6. Crowfoot Wrench

There is no handle for this open-wrench. Rather, the single head is manufactured to attach to a ratchet handle and socket extension, permitting it to fit in really tight positions.

When you do not first want to remove the surrounding parts, they do a lot of work to handle the bolts located deep on the body of the machine.

  • Tightens/loosens bolts
  • Standard and metric sizes
  • Has no handle
  • Operates with a ratchet handle/socket extension combination
  • Designed to work in tight spaces

7. Basin Wrench

Tightens/loosens nuts and hose couplings under sinks and lavatories. This peculiar wrench has a long, T-shaped handle ending in a curved, serrated jaw. Its primary function is to loosen or tighten the fixtures under sinks and toilets, resulting in it also being known as a faucet wrench.

8. Pipe Wrench

As per its name, this spanner is used to fasten or dismantle pipes and their units. Its jaw is made of forging tough steel. On its movable jaw flat threads are cut and on its fixed jaw, a plate is joined with a groove In it.

A knurled round nut is fitted in this groove. On revolving this nut, the movable jaw increases or reduces the size by moving up or down. A spring is fixed between fixed and movable jaw, which helps in the proper grip of the job. Pipe wrenches are made of 6”, 9” and 18”.

  • Turns metal pipes and fittings
  • Moveable upper jaw to adjust wrench size

9. Hex Key/Allen Wrench

Perhaps the most famous key wrench, an Allen wrench is a hexagonal bar bent into an L-shape. Sometimes referred to as a hex key due to the shape, the male ends slot into holes on screws and similar fasteners. For this reason, Allen wrenches often find themselves mixed in with the screwdrivers when stored.

What makes hex screws so darn useful is the fact that children can’t just grab a penny and unscrew the furniture when you’re not looking. Another advantage is the L-shape. You can insert the long end, wrap a finger around the shorter end, and use it for a handle when working with deeper screws.

Conversely, you can insert the short end into the slot and turn the long end, giving you superior torque for those extra-tight screws. Allen wrenches come in either SAE or metric sizes, so there’s less guesswork on which size will function when you’re working with an SAE fastener and Imperial key (or vice-versa).

  • Tightens/loosens hex-head screws and bolts
  • Standard and metric sizes
  • Available as separate wrenches or in sets where the wrenches fold up into a handle
  • Available with T-handles for improved leverage

10. Star-Head Key/Torx Key

Sometimes referred to as a star-headed key, this cousin of the hex key wrench is designed to fit into the star-shaped heads of certain bolts and screws.

While they can be purchased in the same L-shape as the average Allen, you can also purchase these in a housed set that more closely resembles a Swiss army knife than a wrench set.

  • Tightens/loosens six-point, star-head screws and bolts
  • Standard and metric sizes
  • Available as separate wrenches or in sets where the wrenches fold up into a handle

11. Strap Wrench

Tightens loosens and turns a variety of different-sized items that don’t have flat faces (container lids and plumbing fittings) for a standard wrench to grip

Most commonly seen in use for oil filter changing, these have a rubber, fabric, or metal band or chain that loops through a handle. This self-tightening tool works best on round objects that are too greasy or oily for a normal wrench to grip.

12. Chain wrench

In order to fasten or dismantle pipes or round jobs of larger diameter, a chain wrench is used. When the job is held in the wrench it is revolved. A plate having cuts in its mouth is fitted, which is joined with a rivet. Chain drips the job very strongly.

13. Socket Wrench

The socket wrench (or ratchet) uses a ratcheting mechanism to allow you to quickly tighten or loosen the nuts or bolts without removing the wrench from the fastener.

This type of wrench is available with 1/4″, 3/8″ (most common), 1/2″, and 1″ drives, you fit just the right size socket you will need at the top of the drive.

14. Torque wrench

This socket wrench is designed to deliver a specific amount of torque without overtightening. This amount can be calibrated, and different types are available (including manual, digital, and other variations).

It’s most commonly used for automotive work such as tightening wheel lug nuts. Torque sticks may be quicker but not as accurate.

A torque wrench can also be used on bicycles, farming equipment, or any instance where tightening a nut or bolt to a specific torque specification is usually set by the manufacturer.

15. Oil Filter Wrench

Another tool used mainly in the automotive industry, oil filter wrenches actually have four different styles and often have to be matched to the brand of car.

Chain strap and metal strap styles use a loop to wrap around the filter casing, while the more recognizable claw wrench functions similarly to an adjustable wrench.

Finally, socket-style filter wrenches resemble a cup with parts of the sides cut away. These fit onto the bottom of a filter cap and are used with a ratchet handle.

16. Impact Wrench

More closely resembling a cordless drill in appearance, air impact wrenches use an air compressor while cordless impact wrenches use a rechargeable battery. The former is sometimes called air wrenches or air guns.

Part of the socket family, this wrench can apply high torque to remove stubborn nuts or bolts. They are a great choice for handling multiple nuts (such as when mounting wheels on a car), although they are a poor choice for any job that requires precision.

17. Pedal Wrench

Pedal wrenches have a rounded tip with generally one or two U-shaped recesses. As the name implies, the wrench is used for repairs involving pedals. Thus, is it used most often in bicycle repair shops or for fairground rides such as pedal boats?

18. Monkeywrench

This is the type of wrench referred to when speaking of sabotage (i.e., “throwing a wrench/spanner into the works”). It’s an older form of adjustable wrench similar to an alligator wrench, but with smooth jaws and a rounded handle.

Its association with sabotage heralds from its former role as a standard tool in most industrial branches.

19. Pliers Wrench

While the name might not seem familiar, you have likely used these at some point in your life. The flat-edged jaws are at an angle and each is attached to a handle, which is connected by a bolt.

The bolt can slide between two or more positions of an opening on the upper jaw, allowing the wrench to be adjusted to fit different sizes of head. The name comes from the way this tool is gripped, which is the same as a pair of pliers.

20. Plumber’s Wrench

Similar in design to pliers’ wrenches, the jaws are shaped to fit hexagonal nuts. The jaws are adjustable to fit a variety of pipe fittings. It is used exclusively in plumbing for work on pipes and fixtures.

21. Tap Wrench

This key fits the square drive of taps, which are used in cutting female threads (such as those inside a nut).

The shape of these wrenches may be either T-shaped or a double-handled bar with the attachment socket in the middle.

22. Spud Wrench

Another tool that has fallen out of common use, this open-ended wrench had a spike on the opposing end which was used to line up the holes on pipes.

It has since been made obsolete by the plumber’s wrench, although it can still be found in the occasional toolbox.

23. Alligator Wrench

The top jaw of the alligator wrench is serrated, while the rear is smooth. The alligator wrench was identified due to the way it gripped nuts.

The handle of this wrench looks like a pointed fang than a modern pipe wrench. As these were primarily manufactured to handle square-shaped heads, it has become rare to see them outside of films.

24. Basin Wrench

This type of wrench is consisting of a long T-shaped handle in a curved, serrated jaw. Its main purpose is to tighten or loosen the heads under the sink and toilet, consequently, it is also known as a faucet wrench.

25. Armorer’s Wrench

This armorer’s or single-piece wrench consists of a C-shaped, serrated head and involves a square slot and or a hole to attach the ratchet handle.

They are available in many designs and are usually of the specific type or size of the model of gun. These are used for gun repair and maintenance.

26. Dog Bone Wrench

Each side of the dog bone wrench has two box-shaped ends that have a different socket size. This wrench is named after its bone-shaped appearance, which is sometimes called the dumb-bell wrench.

These are only used for bike maintenance, even though their ability to fit in small spaces sometimes makes them useful elsewhere. Some dog bone wrenches have swivel heads for greater flexibility.

27. Drum Key

A drum key or square-holly socket wrench consists of a T-shape with a flattened handle.

As the name suggests, it is used to tune different percussion instruments, such as drums. A drum key with longer handles provides you to apply more torque than shorter handles.

28. Bung Wrench

A drum wrench is a socket-style wrench available in a variety of styles. It is also known as a drum plug wrench. It was specifically manufactured to eliminate the plastic or metal dung (cap) on a drum or barrel.

29. Fan Clutch Wrench

These flat clutch wrenches consist of a U-shaped opening at one end. They are specially designed to remove fan clutches on cars.

Any this type of wrench has a square opening at the other end, providing them to double as a clutch hold tool, while a second wrench is used to turn the hex nut.

30. Hammer Wrench

A hammer wrench is a short, thick wrench that has a block end that is used to strike with a hammer to transmit a greater amount of force. It is also known as a striking wrench.

It is used to tighten large flange fittings and fasteners. A Hammer wrench is also used to release stuck or rusted nuts and bolts through high force. This heavy-duty wrench is used in some metal, plumbing, or electrical jobs.

31. Cone Wrench

Imagine an open-ended wrench after an elephant step on it and you’ll have a cone wrench. These wide, flat wrenches are used on the cone portion of a cup and cone hub.

It’s mostly used for bicycles or adjusting the leveling feet of washing machines, but is sometimes employed on other gentle projects where a normal open-ended wrench is too thick.

32. Tension Wrench

Another one of those wrenches you’ve seen but never heard of, a tension wrench is the “key” component in lockpicking and can be found in a wide range of designs.

They can be rigid or flexible and are used to apply tension while the pick does its job.

If you’ve ever seen someone picking a lock in a movie or video game and wondered why they only moved one of the two tools, the stationary one is the tension wrench.

33. Spoke Wrench

These tiny wrenches are designed for maintaining the spokes on wire wheels. One end has a slot that fits around the spoke, while the other end has a drive head that fits around the nipple nut.

Due to the size and shape, this wrench can be rotated in a full circle without having to remove it.

The most common place to find this tool is a bike repair shop. Some variations more closely resemble a tiny open-ended wrench, while others look more like a piece of curved, flat metal.