American Wire Gauge ( AWG) is a logarithmic stepped standardized wire gauge system used since 1857, predominantly in North America, for the diameters of round, solid, nonferrous, electrically conducting wire. Dimensions of the wires are given in ASTM standard B 258. [1] The cross-sectional area of each gauge is an important factor for determining its current-carrying capacity. Results may change with real wires: different resistivity of material and number of strands in wire in square millimeters (mm 2) is equal to pi divided by 4 times the square wire diameter d in millimeters (mm): d n = 0.005 i n c h × 92 ( 36 − n ) / 39 = 0.127 m m × 92 ( 36 − n ) / 39 {\displaystyle d_{n}=0.005~\mathrm {inch} \times 92 The n gauge wire resistance R in ohms per kilofeet (Ω/kft) is equal to 0.3048×1000000000 times the wire's resistivity ρ in

times one way wire length L in feet (ft) times the wire resistance per 1000 feet R in ohms (Ω/kft) divided by 1000: While the AWG is essentially identical to the Brown & Sharpe (B&S) sheet metal gauge, the B&S gauge was designed for use with sheet metals as its name suggests. These are functionally interchangeable but the use of B&S in relation to wire gauges, rather than sheet metal gauges, is technically improper.The AWG tables are for a single, solid and round conductor. The AWG of a stranded wire is determined by the cross-sectional area of the equivalent solid conductor. Because there are also small gaps between the strands, a stranded wire will always have a slightly larger overall diameter than a solid wire with the same AWG.

one way wire length L in meters (m) times the wire resistance per 1000 meters R in ohms (Ω/km) divided by 1000:

The line to line voltage drop V in volts (V) is equal to square root of 3 times the wire current I in amps (A) times AWG is also commonly used to specify body piercing jewelry sizes (especially smaller sizes), even when the material is not metallic. [2] Formulae [ edit ] Increasing gauge numbers denote logarithmically decreasing wire diameters, which is similar to many other non-metric gauging systems such as British Standard Wire Gauge (SWG). However, AWG is dissimilar to IEC 60228, the metric wire-size standard used in most parts of the world, based directly on the wire cross-section area (in square millimetres, mm²). The AWG originated in the number of drawing operations used to produce a given gauge of wire. Very fine wire (for example, 30gauge) required more passes through the drawing dies than 0gauge wire did. Manufacturers of wire formerly had proprietary wire gauge systems; the development of standardized wire gauges rationalized selection of wire for a particular purpose. one way wire length L in feet (ft) times the wire resistance per 1000 feet R in ohms (Ω/kft) divided by 1000: