The wire gauge is a number that can be found on the cord jacket; it indicates the size of the conducting wires inside the cord. Heavier cords have smaller numbers based on the American Wire Gauge System (AWG). It is typically listed with another number that indicates the number of conducting wires inside the cord. For example, if a label has the number 14/3 listed on it, it is a 14-gauge wire with three conducting wires.
Extension cords can typically be found in four different gauges. A 16-gauge cord is considered light duty, while14-gauge is medium duty and 2-gauge is heavy duty. Some contractor and construction extension cords are found in 10-gauge, which is considered extra heavy duty and is the heaviest grade of cord.
Choosing the Best Cord
When choosing a cord, you must determine what gauge will best suit your needs. As a cord gets longer, the current carrying capacity of the cord gets lowered. A heavier gauge with a smaller AWG number is needed for longer cord lengths and/or higher wattage appliances and tools.