Many electrical connections rely on a terminal (a bolt-down or push-fit connector) with an open end crimped onto the bare end of a wire or cable. The terminals, often simply called crimps, are made of metal and are, usually, shrouded in PVC or nylon. A crimping tool squeezes the crimp shut, forming a secure join between terminal and cable.
Crimps are employed in all kinds of electrical connections, from the push-fit plastics inside your laptop to the metal rings that attach to your car battery. They’re available in a huge range of styles and sizes, but all require being fitted with a crimping tool. Most crimping tools are squeezed like you would a pair of pliers, though they are larger and their mechanisms and jaws vary considerably. Each is designed to suit a specific range of wiring jobs.
The sheer variety on the market can make it a challenge to know which is the best crimping tool for a particular task. So use this guide to understand the types available, the factors and features to keep in mind when shopping, and why the following are considered the best crimping tools you can buy.
- BEST OVERALL: Titan 11477 Ratcheting Wire Terminal Crimper Tool
- BEST BANG FOR THE BUCK: Neiko 02037A Compact 4-in-1 Multi-Purpose
- BEST ELECTRICAL: Wirefy Crimping Tool Insulated Electrical Connectors
- BEST AUTOMOTIVE: TEMCo Hammer Lug Crimper Tool
- BEST HYDRAULIC: WBHome Hydraulic Wire Crimper Battery Lug Terminal
- BEST CRIMPING TOOL KIT: IWISS 5 interchangeable Jaws Crimping tool kit
Cable (or wire) thickness is usually given in American Wire Gauge (AWG) or simply “gauge.” The crimp, also known as the terminal, needs to be a corresponding size for the connection to work properly. At its thinnest, gauge can be around a hundredth of an inch in diameter, though 18 gauge (0.04 inch) is the thinnest in common use. By contrast, the maximum AWG, 4/0, is almost 0.5 inch across. Larger cable diameters are generally given as MCM (which is an abbreviation for “thousands of circular mils”) and can exceed 1.5 inches.
As each cable size can be connected to a variety of different terminals, no single crimping tool can handle every job. There are three basic types of crimping tools: handheld, hydraulic, and hammer.
Handheld crimping tools are the most common. They’re usually very affordable and offer considerable versatility. These crimpers range in size from those designed for high precision work, which sit easily in the palm of a hand, to models more than a foot long that offer the leverage required for heavy-duty crimping.
Although many use a simple squeezing action like ordinary pliers, a ratchet is often employed to provide consistent, repeatable pressure application. Jaws vary to accommodate different types and sizes of terminals. To offer increased range, some handheld crimping tools have interchangeable jaw sets. They may also incorporate wire strippers and/or small bolt cutters, making the tool multipurpose.
While mechanized hydraulic wire crimping tools are available for production lines, most of this type are still manually operated. They use an oil-filled cylinder actuated by a lever, thus dramatically increasing output pressure. Hydraulic crimpers are usually rated by the force they can apply. This is measured in tons per square inch (anywhere from 8 to 16), underlining the terrific power they can generate.
Although frequently used in heavy-duty applications, a hydraulic crimper can handle medium-size terminals, thanks to interchangeable crimping dies; these steel jaws are specially shaped to close the crimp firmly. The tools are usually supplied with a selection of these—a typical example might contain from 8 AWG (0.12 inch) to 0-250 MCM (0.68 inch).
Hydraulic crimping tools are easy to use but do require occasional maintenance. If air gets into the cylinder, for instance, it will reduce performance, so purging may be necessary. Oil seals also need to be changed periodically.
A hammer crimping tool is a basic, low-cost device, often making it best for those who only need a crimper occasionally. However, it is also a robust and compact tool that can put up with tough environments and is often found in automotive shops and wherever else heavy-duty crimping is required.
A hammer crimper doesn’t use dies, but instead consists of a height-adjustable, wedge-shaped ram on a sliding carriage with a V-shaped groove at the base. The crimp and cable to be connected are simply placed in this groove. As the name of this crimper suggests, closing the terminal is a matter of hitting the wedge with a hammer. A 2- to 4-pound sledge hammer is recommended, though any heavy hammer will do. A bench vise could also be used to press the ram onto the crimp.
The mechanical actions mentioned should play a role in your choice, but a number of other factors must be taken into account as well. Read on for details about materials, applications, and more to help you choose the best crimping tool for your wiring projects.
Crimping tools of all types are invariably made of steel. Carbon steel is often cited as offering high durability, but this can be a bit misleading. All steel is a mixture of iron and carbon, so the term “carbon steel” can apply to any of these metals. For increased toughness, look for high carbon steel (a small but important difference) or hardened steel. The latter is especially appropriate in hydraulic and hammer crimping tools because of its resilience to high pressure and repeated impact.
Handheld crimping tools usually have plastic or rubber grips on the handles for added comfort. On cheap crimping tools, this can be quite thin and prone to splitting. Better-quality models frequently have thicker padding and better ergonomics, offering a more secure grip.
DIY and hobby users will often try to find a single tool for multiple applications. It’s perfectly understandable as it helps reduce expense, but improper fit or pressure often results in faults. There really are no “jack of all trades” solutions when it comes to crimping tools, so you’re often best off being specific.
This is particularly true when dealing with specialist connectors. Fortunately it’s not difficult to find a variety of alternatives for every application that include choices ranging from decent budget and professional tools. Contractors often buy several different crimping tools, finding the efficiency and reliability of having the right tool for the job more than makes up for the extra expense.
Crimping tool product descriptions usually offer good guidance, but if you’re unsure of which you need, do further research. Using the wrong type can result in poor connections that eventually lead to a breakdown.
Volume of Operation
In factories and other high-productivity situations, automated machinery is used. Such tooling isn’t typically necessary in most general electrical projects, but volume of operation (or frequency of use) is still an important consideration.
For example, a hammer crimping tool is often found in auto shops for refitting battery cables. If it’s only needed as occasionally as once a month, an inexpensive tool may offer adequate performance and good value. If the same task had to be undertaken several times a day, a hydraulic crimping tool would make more sense. They cost more, but they’re faster and require less effort.
Similarly, a basic handheld crimping tool might suffice for folks who tinker with electrical devices as a hobby. A pro who does the same types of repairs on a daily basis would choose a ratcheting model so every crimp had the same pressure applied, every time. These also release automatically, increasing productivity.
Wire Gauge and Crimp Profile
Hydraulic and hammer crimpers are heavy-duty tools that can handle the largest of wire gauges. The former is limited by the die sizes available, the latter by how much physical force can be applied. Crimp profile—the shape of the crimp before it’s compressed, which varies according to connector type—is unimportant with these tools, because a limited variety is used.
With more general electrical projects, such as repairing household appliances or electronic apparatus, there are a number of different profiles. These include hex, indented, circular, B-Crimp, and others. The profile defines how the crimp closes around the cable, so choosing the right type of jaw is vital in providing secure connections. Most handheld crimping tools will offer a range of cable gauges and should make clear the type of profile they provide. However, it’s not always the case, so it’s always a good idea to check the specification provided by the manufacturer.
Electrical crimp connectors come in dozens of different materials and styles: nylon, PVC, non-insulated, insulated, heat shrinkable, ring, spade, Faston, Lucar, Shur-Plug—the list is extensive.
Many of these descriptions have little impact on the type of crimping tool used, as they define the type of connection being made between two components. However, some types of crimping tools work better with nylon than PVC, for example, making it important to understand the specification of the connector to select a suitable crimper. Often the manufacturer makes this easy, not just by giving clear definitions but also by color coding the jaws so you have rapid visual identification.
Although it’s a good policy to buy a crimping tool that’s as closely matched as possible to the specification of the cable size and crimps you’re using, these tools are not without versatility. Even basic models will handle a variety of cable and connector diameters. Better-quality tools may offer replaceable jaw sets, which give you the opportunity to handle three or four times as many sizes and potentially different types of connectors as well.
Wire stripping is a necessary part of any crimping operation, and some tools incorporate blades for this purpose. Cutters for trimming cable to length may also be included. Crimping tool kits may extend this further with the addition of cable testers or the terminals themselves.
Our Top Picks
The criteria detailed above went into the selection of the following tools, along with the precision and durability of each product.
Busy professionals and enthusiastic amateurs will both appreciate the ease of use, repeatable performance, and excellent value of this Titan wire crimping tool. It’s designed to handle the common insulated nylon terminal type with cable diameters from 22 AWG up to 10 AWG. The double crimp die provides extra cable security. Jaws are color-coded for rapid identification and high productivity.
The ratcheting action provides great control when tightening and can generate tremendous power, yet the action is light so hands won’t tire quickly. That’s helped by ergonomic handles that incorporate a useful quick-release lever for those occasional jams.
The Neiko 4-in1 crimper can grip, bend, strip, and crimp both insulated and non-insulated connectors from 20 AWG up to 12 AWG. At 7 inches long, this versatile, well-priced device fits easily into a tool box, yet it provides sufficient leverage to apply plenty of force when crimping.
Durability comes by way of forged alloy steel that is hammered into shape under pressure while still molten metal, making these preferable to cheap wire crimpers that are often just punched out of sheet metal. Cutting edges are heat treated and CNC-machined to stay sharp longer. The grips could be more comfortable, but that’s a minor drawback on an otherwise versatile tool that has few rivals for the money.
This crimping tool from Wirefy has been specifically designed for rapid productivity when working with common nylon electrical terminals. The color-coded die allows for quick positioning of the crimp, and double jaws create a high-strength connection. Light pressure holds the terminal in place without the operator needing to maintain grip. A star wheel sets precise crimping pressure, which the ratchet action applies quickly and with repeatable precision. The finished crimp is then auto-released.
The Wirefy crimping tool handles sizes from 22 AWG to 10 AWG. Well-cushioned, nonslip handles provide for high levels of comfort through long work periods.
Modern automotive circuitry allows for little intervention by mechanics or engineers—mostly, it’s a question of identifying the fault and replacing the board. However, battery terminals still get damaged or frayed. The TEMCo hammer crimper provides an easy-to-use, highly durable solution and a straightforward, cost-effective method for low-volume situations.
There’s no need to worry about dies fitting incorrectly, since terminals simply rest in the V-shaped jaw. The crimping ram is then struck with a hammer or tightened in a bench vise. The ram is designed to accommodate wire sizes from 8 AWG all the way up to 4/0 AWG, making the TEMCo hammer lug crimper equally suitable for attaching heavy-duty terminals to welding equipment cables.
The challenge when dealing with heavy-duty crimping tasks is the consistent application of sufficient pressure for a reliable hold. Standard handheld crimpers simply aren’t strong enough and hammer crimpers are relatively slow. The 8-ton hydraulic crimping tool from WBHome offers impressive power, speed, and repeatability while also being straightforward to use.
The crimper comes with a set of eight dies, which slot easily into the hardened steel head, to tackle sizes from 8 AWG up to 4/0 AWG. A squeeze of the rubber-gripped handle applies force, which is automatically released when the required pressure is reached, and a safety valve prevents this from being exceeded. There’s even a tough plastic case included for convenient storage and transportation.
Iwiss produces a wide range of cable tools for both home and professional use and has a reputation for reliability and accurate manufacture. This versatile kit comprises wire strippers, crimpers, four sets of interchangeable jaws, plus a screwdriver, meaning you won’t need to go hunting for one when you want to change the jaws.
Suitable for fitting both non-insulated and insulated terminals, it can strip and crimp wire sizes from 22 AWG to 10 AWG. The variable ratchet action delivers consistent pressure, and ergonomic handles provide hand comfort. The kit comes in a wear-resistant Oxford fabric bag and given the comprehensive nature and the overall quality it’s an affordable choice.
Those new to crimping tools may still want more info on how to shop for and use them. Check out the answers to commonly asked questions below.
Q. What is wire crimping?
Crimping securely attaches electrical connectors to relevant cable. Types and sizes can vary enormously, from those on computer circuit boards to mains (the high-voltage cables that bring power to your home).
Q. Is soldering better than crimping?
It’s not a matter of better; it’s about doing what’s appropriate for the project. Soldering is largely used for attaching wires permanently, whereas crimping is common for connections that can be disassembled.
Q. How do I choose a crimping tool?
The most important considerations are ensuring the tool can handle the type of terminal you need to attach as well as the appropriate wire sizes.