American Wire Gauge (AWG)

What is American Wire Gauge (AWG)?

American Wire Gauge (AWG, sometimes called the Brown & Sharpe wire gauge) is the standardized wire gauge system used to measure the size of electric conducting wire in the United States since 1857. AWG refers to wire made with a solid metal core. It is represented as a simple number that is calculated by finding the radius of the wire, squaring that number, and multiplying it by pi (AWG = πr²). The smaller the number is, the thicker the cable will be.

Stranded wire is also commonly referred to using AWG, but it a little more complex. Because standard cables are made using multiple wires instead of a single solid core, they can be given multiple numbers. For example, a cable called “24 AWG (7x32)” means that the overall outer diameter is 24 AWG but on the inside, the cable has seven 32 AWG wires.

Common Wire Gauges

Certain types of cables will always be the same AWG. For example, RG58 cable is always made as a 20 AWG cable regardless of manufacturer. Coax cables tend to be the same size across the board with different connectors made for the different kinds of cables. There are a few exceptions, such as cables with Quad Shielding being a little thicker and needing special connectors, but these are few and far between.

On the other side of that, there are some cables that come in different variants and as a result, can have different AWGs. Ethernet cable is a prime example for this. Standard ethernet cable is typically 23 or 24 AWG from most manufacturers. However, you also have versions like slim ethernet (30 AWG) and flat ethernet (32 AWG).

Some cables are available in multiple AWGs, with the AWG you need depending on exactly where and how the cable will be installed. Speaker wire is available from 10 to 22 AWG, although most people stick with somewhere from 14 to 18 AWG. Thicker cables have low resistance and are better for long distance runs, but thinner cables have greater flexibility with an increased bend radius.

Wire Size Chart

AWG is typically listed in the name or description of a cable online. It is also commonly listed on the spec sheet for the cable. If you already have the cable and are trying to figure out the AWG, most manufacturers will have it written on the outside jacket. Otherwise, you can take a ruler or similar tool to measure the diameter and refer to the chart below.

Wire Gauge Chart
Wire Size Chart
American Wire Gauge

Other factors related to AWG, such as resistance, can be found using this calculator.