Wire Gauge Sizes

What is the definition of Wire Gauge?

Wire/cable thickness is defined in terms of gauge.  Generally speaking,  the smaller the gauge number, the thicker the cable.  The standardized method of measuring the thickness of a cable (American Wire Gauge or AWG) was established in 1857 in the United States.  This form of measuring cable thickness is used specifically for electrically conductive wire.  Note that the diameter of the cable does not include the outer insulation – just the conducting wire on the inside.

Gauge Terminology

• The term “gauge” is used for wire up to 1 AWG
• The term “aught” (zero) is used for wire 1/0 AWG and larger.  The number “0” in the size is “aught”