American wire gauge - Definition and Overview

American wire gauge (AWG) is a way of specifying wire sizes, where each gauge represents a different wire diameter. It was originally applied to non-ferrous, conducting wire, but lately is commonly used to specify body piercing jewelry sizes in the United States.

In common with many non-metric gauging systems, the measurement involved (wire diameter in this case) decreases with increasing gauge number.

Media:Gauge_Chart.pdf Chart comparing all known wire gauges to each other

Formulas

1 inch = 25.4 mm

<math>D = \frac{ \left ( \frac{92 ^ {36-AWG}}{39} \right ) }{200}<math>

<math>\log(D) = \frac{36-AWG}{39}*\log(92)-\log(200)<math>

<math>AWG = 36 - \frac{39*log(200D)}{\log(92)}<math>

NOTE: The dimension of D is in inches

Table of AWGs and approximate corresponding sizes

The following applies to solid wires. Stranded wires are calculated by calculating the equivalent cross-sectional area.

In the U.S electrical industry, conductors larger than 4/0 AWG are generally identifed by the area in thousands of circular mils ('mcm). (A circular mil is the area of a wire one mil in diameter.) One million circular mils (1000 mcm) is the area of a rod 1000 mils (one inch) in diameter.

Outside the U.S., wire is typically specified in terms of its area in mm².

A few cross-references between AWG and metric stranded wire:

24AWG 

7/0.2

20AWG 

16/0.2

18AWG 

24/0.2