AWG Wire Size Chart

American wire gauge is a standard system for determining the size of copper and aluminum conductors. It uses a number to indicate the diameter of the conductor, and for every six steps in gauge, the wire diameter doubles.

Wire gauge sizes are typically expressed in circular mil (CM). This makes comparing wires of similar diameters much easier than using a formula or relying on a rule of thumb.
Diameter

A wire’s diameter is an important factor in determining its current-carrying capability. Larger diameters can carry higher currents than smaller ones. However, longer wires can have more resistance due to the length of distance they must travel before reaching their destination. This can degrade the signal or current, which is why it’s important to select a wire with a suitable diameter.

Wire diameter is measured based on the outside diameter and cross-sectional area of the conductor without the insulation. AWG numbers are logarithmic stepped standardized systems used since 1857 in North America to note the diameter of round, solid, non-ferrous electrical wires. The general rule of thumb is that each gauge decrease doubles the wire’s diameter and quadruples its cross-sectional area.

The table below shows the diameters of each AWG size, as well as the corresponding ampacity values. The table also includes a conversion to metric gauge, which is useful for international projects. The diameter of the wire is measured in circular mils (also known as a million circular mils or MCM), while the cross-sectional area is calculated using formulas based on the AWG number.
Cross-sectional area

The diameter and cross-sectional area of a wire determine its current-carrying capability. A wire with a smaller diameter has a higher conductivity than a wire with a larger one. The diameter of a solid copper AWG wire is defined by its outer dimension and the size of its gaps. This is a significant difference from stranded wires, where the AWG gauge depends on the overall layout of the individual wires.

The AWG wire gauge is an American standardized system that measures the diameters of round, solid, nonferrous electrically conducting wires. Its numbers range from 0000 to 36, and each successive number corresponds to a geometrically larger diameter.

When calculating the resistance of a wire, you can use the AWG wire gauge chart to find the appropriate gauge for your application. Then, multiply the wire’s resistivity by its cross-sectional area to obtain the total resistance per foot. Finally, divide the total resistance by the wire’s length to obtain the current-carrying capacity.
Resistance

The resistance of a wire depends on its diameter and cross-sectional area. For solid round wires, the diameter can be easily measured using a wire gauge tool. Simply remove the insulation and insert the conductor into the gauge slot. The number printed on the gauge indicates the exact gauge size of the wire. For stranded wires, the numbering system is slightly different. The overall AWG number of the strands is given by a combination of the AWG number of each individual strand and the AWG number of the overall bundle. For example, a 22 AWG 7/30 stranded wire has the overall AWG of 30 and seven individual strands.

In some applications, conductors need to be larger than the practical size limit for round wire. In such cases, thick bars of solid metal called busbars are used as conductors. These are usually made of copper or aluminum and are uninsulated. Their resistance is inversely proportional to the AWG integers.
Ampacity

The capacity of a wire is important to know because it describes the maximum current it can safely carry. Thicker wires have higher capacities than thinner ones. This is because thicker wires have a lower resistance. They can also support higher frequencies of skin depth. Wires are rated according to their AWG integers. These tables and charts are a handy tool for electrical installation systems, as they indicate the proper size of wire to use in various applications.

AWG is a standard system that assigns integers to wire sizes, with 0AWG having the largest diameter and 44AWG having the smallest. These integers correspond to the sizes of round, solid copper wires. AWG tables and charts show important parameters, including diameter, cross-sectional area, resistance, and ampacity. They are also useful in determining the ideal wattage for different appliances. For example, if you’re installing a water heater, you may need a wire with a higher capacity than a light bulb.awg wire size chart