What is a Wire Gauge?

Four core armored cooper cable

A wire gauge is a measurement that determines both the physical size and current capacity for a given wire. Signified by both “gauge” and “AWG (American Wire Gauge)”, this designation enables electricians to choose the correct wire for a particular project, for failing to use the right gauge can lead to major issues. Discover the difference between gauge sizes and more with this guide from Gateway Cable Company. 

Difference Between Wire Gauge Sizes 

In American wire gauge sizes, a fixed measurement signifies how much current a wire can handle. Gauge size numbers are inversely proportional to the wire’s diameter, meaning that the smaller the number, the larger the diameter will be. For example, the smallest AWG is 0000-gauge which correlates to a 11.68mm diameter, while the largest AWG is 26-gauge at 0.40mm. 

What Are the Most Commonly Used Gauge Sizes?

The most common American wire gauge sizes are: 

  • 14-gauge 
  • 12-gauge
  • 10-gauge 
  • 8-gauge 
  • 6-gauge 
  • 2-gauge 

Asking what is the most commonly used gauge size is one thing. Asking about the difference between gauge sizes is another. The difference between wire gauge sizes indicates whether or not a wire can support an electrical application. Evaluating what a wire is made from is another important consideration. Different wires serve different purposes, so knowing how much current can safely pass through a wire is key. 

How to Choose the Correct Wire Gauge Size  

To avoid damage and electrical issues, educate yourself on the specific current capacity related to your project. Below are examples of wire gauge sizes and common home and industrial uses: 

  • 18-gauge: lamp cords and low-voltage lighting around 10 amps
  • 16-gauge: light-duty extension cords around 13 amps
  • 14-gauge: lighting circuits, light fixtures, and lamps around 15 amps
  • 12-gauge: bathroom and kitchen projects, along with 120-volt air conditioners and outdoor receptacles around 20 amps
  • 10-gauge: electric clothes dryers and water heaters, as well as 240-volt window air conditioners around 30 amps
  • 6-gauge: cooktops and ranges around 40-50 amps
  • 4-gauge: large electric heaters and electric furnaces around 60 amps

People often ask us questions about what gauge size should be used with specific appliances. For instance, we get asked “What gauge size do I need for stoves?” and “What gauge size for lamps?” — the best rule of thumb to remember when it comes to American wire gauge sizes is that the smaller the number, the bigger the current it can carry. That’s why cooktops and stoves generally use something like 6 gauge wire whereas small appliances like lamps can make do with 18 gauge wire. It’s always a good idea to research how much capacity a given wire gauge can handle before starting electrical work. 

Find the Right Wire Gauge Gateway Cable Company

If you need more help determining what is a wire gauge and which size is right for your project, contact the experts at Gateway Cable Company. We offer military-grade electrical equipment and cable assembly for a variety of needs and can help point you in the right direction.