AWG means American Wire Gauge,  and is a method to categorize wire size by a "number" instead of diameter. 

In America the AWG was designed logaritmic, because all electricians know how that works (oops...).

By lowering the AWG number with a factory THREE,  you lower the wire resistance with a factory TWO.  You can just hold on to this. Also it means that the step from AWG2 to AWG1 is the same size as the step from AWG33 to AGW32.   One point is rougly 26% change in resistance, regardless at what AWG number you are, or if you go up or down.  This a nice and remarkably good system, bypassing the international standardization mess.  It works in inch or in milimeters the same way, but for NIH reasons, this system is USA only. 

 
AWG to Metric Conversion Chart
Resistance table at 20°C = 68°F
AWG Number Ø [Inch] Ø [mm] Ø [mm²] Copper 
Resistance
[Ohm/m]		 Pure Silver 
Resistance
[Ohm/m]
4/0 = 0000 0.460  11.7  107  0.000161 
3/0 = 000  0.410  10.4  85.0  0.000203 
2/0 = 00  0.365  9.26  67.4  0.000256 
1/0 = 0  0.325  8.25  53.5  0.000323 
1  0.289  7.35  42.4  0.000407 
2  0.258  6.54  33.6  0.000513 
3  0.229  5.83  26.7  0.000647 
4  0.204  5.19  21.1  0.000815 
5  0.182  4.62  16.8  0.00103 
6  0.162  4.11  13.3  0.00130 
7  0.144  3.66  10.5  0.00163 
8  0.128  3.26  8.36  0.00206 
9  0.114  2.91  6.63  0.00260 
AWG Number Ø [Inch] Ø [mm] Ø [mm²] Copper 
Resistance
[Ohm/m]		 Pure Silver 
Resistance
[Ohm/m]
10  0.102  2.59  5.26  0.00328 
11  0.0907  2.30  4.17  0.00413 
12  0.0808  2.05  3.31  0.00521 
13  0.0720  1.83  2.62  0.00657 
14  0.0641  1.63  2.08  0.00829 
15  0.0571  1.45  1.65  0.0104 
16  0.0508  1.29  1.31  0.0132 
17  0.0453  1.15  1.04  0.0166 
18  0.0403  1.02  0.823  0.0210 
19  0.0359  0.912  0.653  0.0264 
AWG Number Ø [Inch] Ø [mm] Ø [mm²] Copper 
Resistance
[Ohm/m]		 Pure Silver 
Resistance
[Ohm/m]
20  0.0320  0.812  0.518  0.0333 
21  0.0285  0.723  0.410  0.0420 
22  0.0253  0.644  0.326  0.0530 
23  0.0226  0.573  0.258  0.0668 
24  0.0201  0.511  0.205  0.0842 
25  0.0179  0.455  0.162  0.106 
26  0.0159  0.405  0.129  0.134 
27  0.0142  0.361  0.102  0.169 
28  0.0126  0.321  0.0810  0.213 
29  0.0113  0.286  0.0642  0.268 
AWG Number Ø [Inch] Ø [mm] Ø [mm²] Copper 
Resistance
[Ohm/m]		 Pure Silver 
Resistance
[Ohm/m]
30  0.0100  0.255  0.0509  0.339 
31  0.00893  0.227  0.0404  0.427 
32  0.00795  0.202  0.0320  0.538 
33  0.00708  0.180  0.0254  0.679 
34  0.00631  0.160  0.0201  0.856 
35  0.00562  0.143  0.0160  1.08 
36  0.00500  0.127  0.0127  1.36 
37  0.00445  0.113  0.0100  1.72 
38  0.00397  0.101  0.00797  2.16 
39  0.00353  0.0897  0.00632  2.73 
40  0.00314  0.0799  0.00501  3.44 


 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

* NIH = Not Invented Here.   General rule,  used by standardization comittees all over the globe, meaning a national standard must be uncompatible with foreign standards.  Otherwise it would not be national, and can not be adopted as such.
 
 
 
 
 
 
 
 
 
 
 
 

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