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Have you ever wondered how different wire gauges compare in size and resistance? This article explores the American Wire Gauge (AWG) system, detailing its history, the significance of gauge numbers, and how wire diameters change with each step. By reading, you’ll gain a clearer understanding of wire specifications, helping you choose the right gauge for your projects and ensuring efficient electrical performance. Dive into the world of wire gauges and discover the precise measurements that keep our electrical systems running smoothly.
AWG (American Wire Gauge) is a standard for distinguishing wire diameters, also known as the Brown & Sharpe wire gauge.
This standardized wire gauge system began to be used in the United States in 1857. The number in front of AWG (such as 24 AWG, 26 AWG) represents the number of holes a wire has to pass through before it reaches its final diameter.
The larger the number, the more holes the wire passes through, and the smaller the diameter of the wire. SWG (Standard Wire Gauge) is one of the standards in the wire and cable industry. BWG (Birmingham Wire Gauge) refers to the Birmingham wire gauge, which indicates the thickness or diameter of the material.
WireGauge | SWG | BWG | BG | AWG | ||||
Inch | mm | Inch | mm | Inch | mm | Inch | mm | |
7/0 | 0.5 | 12.7 | — | — | 0.6666 | 16.932 | — | — |
6/0 | 0.464 | 11.786 | — | — | 0.625 | 15.875 | 0.58 | 14.732 |
5/0 | 0.432 | 10.973 | 0.5 | 12.7 | 0.5883 | 14.943 | 0.5165 | 13.119 |
4/0 | 0.4 | 10.16 | 0.454 | 11.532 | 0.5416 | 13.757 | 0.46 | 11.684 |
3/0 | 0.372 | 9.449 | 0.425 | 10.795 | 0.5 | 12.7 | 0.4096 | 10.404 |
2/0 | 0.348 | 8.839 | 0.33 | 9.652 | 0.1152 | 11.308 | 0.3648 | 9.266 |
0 | 0.324 | 8.23 | 0.34 | 8.639 | 0.3954 | 10.069 | 0.3249 | 8.252 |
1 | 0.3 | 7.62 | 0.3 | 7.62 | 0.3532 | 8.971 | 0.2893 | 7.348 |
2 | 0.276 | 7.01 | 0.284 | 7.214 | 0.3147 | 7.993 | 0.2576 | 6.544 |
3 | 0.252 | 6.401 | 0.259 | 6.579 | 0.2804 | 7.122 | 0.2294 | 5.827 |
4 | 0.232 | 5.893 | 0.238 | 6.045 | 0.25 | 6.35 | 0.2043 | 5.189 |
5 | 0.212 | 5.385 | 0.22 | 5.588 | 0.2225 | 5.652 | 0.1819 | 4.621 |
6 | 0.192 | 4.877 | 0.203 | 5.156 | 0.1981 | 5.032 | 0.162 | 4.115 |
7 | 0.176 | 4.47 | 0.18 | 4.572 | 0.1764 | 4.481 | 0.1443 | 3.665 |
8 | 0.16 | 4.046 | 0.165 | 4.191 | 0.157 | 3.988 | 0.1285 | 3.264 |
9 | 0.144 | 3.658 | 0.148 | 3.759 | 0.1398 | 3.551 | 0.1144 | 2.906 |
10 | 0.128 | 3.251 | 0.134 | 3.404 | 0.125 | 3.175 | 0.1019 | 2.588 |
11 | 0.116 | 2.946 | 0.12 | 3.048 | 0.1313 | 2.827 | 0.0907 | 2.305 |
12 | 0.104 | 2.642 | 0.109 | 2.769 | 0.0991 | 2.517 | 0.0808 | 2.053 |
13 | 0.092 | 2.337 | 0.095 | 2.413 | 0.0882 | 2.24 | 0.072 | 1.828 |
14 | 0.08 | 2.032 | 0.083 | 2.108 | 0.0785 | 1.994 | 0.0648 | 1.628 |
15 | 0.072 | 1.829 | 0.072 | 1.829 | 0.0699 | 1.775 | 0.0571 | 1.45 |
16 | 0.064 | 1.626 | 0.065 | 1.651 | 0.0625 | 1.588 | 0.0508 | 1.291 |
17 | 0.056 | 1.422 | 0.058 | 1.473 | 0.0556 | 1.412 | 0.0453 | 1.15 |
18 | 0.048 | 1.219 | 0.049 | 1.245 | 0.0495 | 1.257 | 0.0403 | 1.024 |
19 | 0.04 | 1.016 | 0.042 | 1.067 | 0.044 | 1.118 | 0.0359 | 0.912 |
20 | 0.036 | 0.914 | 0.035 | 0.839 | 0.0392 | 0.996 | 0.032 | 0.812 |
21 | 0.032 | 0.813 | 0.032 | 0.813 | 0.0349 | 0.887 | 0.0285 | 0.723 |
22 | 0.028 | 0.711 | 0.028 | 0.711 | 0.03125 | 0.794 | 0.02535 | 0.644 |
23 | 0.024 | 0.61 | 0.025 | 0.635 | 0.02782 | 0.707 | 0.0201 | 0.573 |
24 | 0.022 | 0.559 | 0.022 | 0.559 | 0.02476 | 0.629 | 0.0179 | 0.511 |
25 | 0.02 | 0.508 | 0.02 | 0.508 | 0.02204 | 0.56 | 0.01594 | 0.455 |
26 | 0.018 | 0.457 | 0.018 | 0.457 | 0.01961 | 0.498 | 0.0142 | 0.405 |
27 | 0.0164 | 0.417 | 0.016 | 0.406 | 0.1745 | 0.443 | 0.0142 | 0.361 |
28 | 0.0149 | 0.376 | 0.014 | 0.356 | 0.01562 | 0.397 | 0.01264 | 0.321 |
29 | 0.0136 | 0.345 | 0.013 | 0.33 | 0.0139 | 0.353 | 0.01126 | 0.286 |
30 | 0.0124 | 0.315 | 0.012 | 0.305 | 0.0123 | 0.312 | 0.01003 | 0.255 |
31 | 0.0116 | 0.295 | 0.01 | 0.254 | 0.011 | 0.27 | 0.00893 | 0.227 |
32 | 0.0109 | 0.274 | 0.009 | 0.229 | 0.0098 | 0.249 | 0.00795 | 0.202 |
33 | 0.01 | 0.254 | 0.008 | 0.203 | 0.0087 | 0.221 | 0.00708 | 0.18 |
34 | 0.0092 | 0.234 | 0.007 | 0.178 | 0.0077 | 0.196 | 0.0063 | 0.16 |
35 | 0.0084 | 0.213 | 0.005 | 0.127 | 0.0069 | 0.175 | 0.00561 | 0.143 |
36 | 0.0076 | 0.193 | 0.004 | 0.102 | 0.0061 | 0.155 | 0.005 | 0.127 |
37 | 0.0068 | 0.173 | 0.0054 | 0.137 | 0.00445 | 0.113 | ||
38 | 0.006 | 0.152 | 0.0048 | 0.122 | 0.00396 | 0.101 | ||
39 | 0.0052 | 0.132 | 0.0043 | 0.109 | 0.00353 | 0.09 | ||
40 | 0.0048 | 0.122 | 0.00386 | 0.098 | 0.00314 | 0.08 | ||
41 | 0.0044 | 0.112 | 0.00343 | 0.087 | 0.0028 | 0.071 | ||
42 | 0.004 | 0.102 | 0.00306 | 0.078 | 0.00249 | 0.063 | ||
43 | 0.0036 | 0.091 | 0.00272 | 0.069 | 0.00222 | 0.056 | ||
44 | 0.0032 | 0.081 | 0.00242 | 0.061 | 0.00198 | 0.05 | ||
45 | 0.0028 | 0.071 | 0.00215 | 0.055 | 0.00176 | 0.048 | ||
46 | 0.0024 | 0.061 | 0.00192 | 0.049 | 0.00157 | 0.046 | ||
47 | 0.002 | 0.051 | 0.0017 | 0.043 | 0.0014 | 0.035 | ||
48 | 0.0016 | 0.041 | 0.00152 | 0.039 | 0.00124 | 0.032 | ||
49 | 0.0012 | 0.03 | 0.00135 | 0.034 | 0.00111 | 0.028 | ||
50 | 0.001 | 0.025 | 0.0012 | 0.03 | 0.00099 | 0 |
Resistivity is a physical quantity used to represent the electrical resistance characteristics of various materials. The resistance of a wire made of a certain material, 1 meter long, with a cross-sectional area of 1 square millimeter, and at room temperature (20℃), is called the resistivity of this material.
According to Ohm’s Law: R=PL/S, the resistance of the conductor can be calculated. R is resistance, in ohms. P is resistivity, in ohm-meters, and is related to the material of the conductor. L is the length of the conductor, in meters. S is the cross-sectional area of the conductor, in square meters.
Gauge | Inches | Diameter | Crosssect.Area | ConductorResistance DCR@20℃ | Weight | ||||
AWG | mils | mm | Circ.mils | Sq.mm | ohms/M | Ohms/km | Lbs./m | kg/km | |
40 | 0.0031 | 3.1 | 0.079 | 9.6 | 0.0049 | 1080 | 3540 | 0.0291 | 0.0433 |
39 | 0.0035 | 3.5 | 0.089 | 12.3 | 0.0062 | 847 | 2780 | 0.0371 | 0.0552 |
38 | 0.004 | 4 | 0.102 | 16 | 0.0081 | 648 | 2130 | 0.0484 | 0.72 |
37 | 0.0045 | 4.5 | 0.114 | 20.3 | 0.0103 | 512 | 1680 | 0.0613 | 0.0912 |
36 | 0.005 | 5 | 0.127 | 25 | 0.0127 | 415 | 1360 | 0.0757 | 0.113 |
35 | 0.0056 | 5.6 | 0.142 | 31.4 | 0.0159 | 331 | 1080 | 0.0949 | 0.141 |
34 | 0.0063 | 6.3 | 0.16 | 39.7 | 0.0201 | 261 | 857 | 0.12 | 0.179 |
33 | 0.0071 | 7.1 | 0.18 | 50.4 | 0.0255 | 206 | 675 | 0.153 | 0.228 |
32 | 0.008 | 8 | 0.203 | 64 | 0.0324 | 162 | 532 | 0.194 | 0.289 |
31 | 0.0089 | 8.9 | 0.226 | 79.2 | 0.0401 | 131 | 430 | 0.24 | 0.357 |
30 | 0.01 | 10 | 0.254 | 100 | 0.0507 | 104 | 340 | 0.303 | 0.451 |
29 | 0.0113 | 11.3 | 0.287 | 128 | 0.0649 | 81.2 | 266 | 0.387 | 0.576 |
28 | 0.0126 | 12.6 | 0.32 | 159 | 0.0806 | 65.3 | 214 | 0.481 | 0.716 |
27 | 0.0142 | 14.2 | 0.361 | 202 | 0.102 | 51.4 | 169 | 0.61 | 0.908 |
26 | 0.0159 | 15.9 | 0.404 | 253 | 0.128 | 41 | 135 | 0.765 | 1.14 |
25 | 0.0179 | 17.9 | 0.455 | 320 | 0.162 | 32.4 | 106 | 0.97 | 1.44 |
24 | 0.0201 | 20.1 | 0.511 | 404 | 0.205 | 25.7 | 84.2 | 1.22 | 1.82 |
23 | 0.0266 | 22.6 | 0.574 | 511 | 0.259 | 20.3 | 66.6 | 1.55 | 2.31 |
22 | 0.0253 | 25.3 | 0.643 | 640 | 0.324 | 16.2 | 53.2 | 1.94 | 2.89 |
21 | 0.0285 | 28.5 | 0.724 | 812 | 0.411 | 12.8 | 41.9 | 2.46 | 3.66 |
20 | 0.032 | 32 | 0.813 | 1020 | 0.519 | 10.1 | 33.2 | 3.1 | 4.61 |
19 | 0.0359 | 35.9 | 0.912 | 1290 | 0.653 | 8.05 | 26.4 | 3.9 | 5.8 |
18 | 0.0403 | 40.3 | 1.02 | 1620 | 0.823 | 6.39 | 21 | 4.92 | 7.32 |
17 | 0.0453 | 45.3 | 1.15 | 2050 | 1.04 | 5.05 | 16.6 | 6.21 | 9.24 |
16 | 0.0508 | 50.8 | 1.29 | 2580 | 1.31 | 4.02 | 13.2 | 7.81 | 11.6 |
15 | 0.0571 | 57.1 | 1.45 | 3260 | 1.65 | 3.18 | 10.4 | 9.87 | 14.7 |
14 | 0.0641 | 64.1 | 1.63 | 4110 | 20.8 | 2.52 | 8.28 | 12.4 | 18.5 |
13 | 0.072 | 72 | 1.83 | 5180 | 2.63 | 2 | 6.56 | 15.7 | 23.4 |
12 | 0.0808 | 80.8 | 2.05 | 6530 | 3.31 | 1.59 | 5.21 | 19.8 | 29.5 |
11 | 0.0907 | 90.7 | 2.3 | 8230 | 4.17 | 1.26 | 4.14 | 24.9 | 37.1 |
10 | 0.1019 | 101.9 | 2.588 | 10380 | 5.26 | 0.9988 | 3.23 | 31.4 | 46.8 |
9 | 0.1144 | 114.4 | 2.906 | 13090 | 6.63 | 0.7925 | 2.6 | 39.6 | 59 |
8 | 0.1285 | 128.5 | 3.265 | 16510 | 8.37 | 0.6281 | 2.061 | 50 | 74.4 |
7 | 0.1443 | 144.3 | 3.655 | 20820 | 10.55 | 0.4981 | 1.634 | 63 | 93.8 |
6 | 0.162 | 162 | 4.115 | 26240 | 13.3 | 0.3952 | 1.296 | 79.4 | 118 |
5 | 0.1819 | 181.9 | 4.62 | 33090 | 16.77 | 0.3134 | 1.028 | 100 | 149 |
4 | 0.2043 | 204.3 | 5.189 | 41740 | 21.15 | 0.2485 | 0.8152 | 126 | 188 |
3 | 0.2294 | 229.4 | 5.827 | 52620 | 26.67 | 0.1917 | 0.6466 | 159 | 237 |
2 | 0.2576 | 257.6 | 6.543 | 66360 | 33.62 | 0.1563 | 0.5128 | 201 | 299 |
1 | 0.2893 | 289.3 | 7.348 | 83690 | 42.41 | 0.1239 | 0.4065 | 253 | 377 |
1/0 | 0.3249 | 324.9 | 8.252 | 105600 | 53.49 | 0.03925 | 0.3223 | 319 | 476 |
2/0 | 0.3648 | 364.8 | 9.266 | 133100 | 67.43 | 0.07793 | 0.2557 | 403 | 599 |
3/0 | 0.4096 | 409.6 | 10.4 | 167800 | 85.01 | 0.06182 | 0.2028 | 508 | 756 |
4/0 | 0.46 | 460 | 11.68 | 211600 | 107.22 | 0.04901 | 0.1608 | 641 | 953 |
AWG | Diameter | Area | Weight Kg/km | No./mm | |||||
Mils | mm | C.M. | in2 | mm2 | |||||
1 | 289.3 | 7.348 | 83.694 | 0.06573 | 42.41 | 377 | 1/7.349 | ||
8.508 | 379 | 19/1.690 | |||||||
8.500 | 379 | 37/1.210 | |||||||
8.480 | 377 | 61/0.941 | |||||||
2 | 257.6 | 6.544 | 66.358 | 0.05212 | 33.63 | 299 | 1/6544 | ||
7.410 | 299 | 7/2.474 | |||||||
7.551 | 299 | 19/1.502 | |||||||
7.590 | 302 | 37/1.080 | |||||||
4 | 204.3 | 5.189 | 41.738 | 0.03278 | 21.15 | 188 | 1/5.190 | ||
5.960 | 188 | 7/1.962 | |||||||
5.991 | 188 | 19/1.191 | |||||||
5.992 | 188 | 37/0.854 | |||||||
6.032 | 188 | 133/0.450 | |||||||
6.036 | 192.2 | 420/0.254 | |||||||
6 | 162 | 4.115 | 26.244 | 0.0 2061 | 13.3 | 118.2 | 1/4.116 | ||
4.770 | 119.0 | 7/1.560 | |||||||
4.829 | 120.0 | 19/0.950 | |||||||
4.749 | 118.0 | 37/0.677 | |||||||
4.803 | 121.0 | 266/0.254 | |||||||
8 | 128.5 | 3.264 | 16.512 | 0.01297 | 8.368 | 74.39 | 1/3.265 | ||
3.690 | 74.43 | 7/1.234 | |||||||
3.771 | 74.60 | 19/0.749 | |||||||
3.760 | 74.40 | 37/0.537 | |||||||
3.783 | 75.00 | 133/0.284 | |||||||
10 | 101.9 | 2.588 | 10.384 | 0.008156 | 5.262 | 46.78 | 1/2.589 | ||
2.961 | 46.94 | 7/0.980 | |||||||
3.005 | 47.40 | 19/0.595 | |||||||
3.017 | 47.80 | 105/0.254 | |||||||
2.974 | 46.40 | 259/0.160 | |||||||
12 | 80.81 | 2.053 | 6.53 | 0.005129 | 3.309 | 29.42 | 1/2.053 | ||
2.325 | 29.43 | 7/0.776 | |||||||
2.371 | 29.37 | 19/0.471 | |||||||
2.365 | 29.58 | 65/0.254 | |||||||
2.395 | 30.10 | 168/0.160 | |||||||
14 | 64.08 | 1.628 | 4.106 | 0.003225 | 2.081 | 18.50 | 1/1.630 | ||
1.845 | 18.53 | 7/0.616 | |||||||
1.877 | 18.50 | 19/0.374 | |||||||
1.885 | 18.66 | 41/0.254 | |||||||
1.894 | 18.81 | 105/0.160 | |||||||
16 | 50.82 | 1.291 | 2.583 | 0.00 2029 | 1.309 | 11.64 | 1/1.291 | ||
1.464 | 11.67 | 7/0.488 | |||||||
1.502 | 11.83 | 26/0.254 | |||||||
1.483 | 11.65 | 65/0.160 | |||||||
18 | 40.3 | 1.024 | 1.624 | 0.001275 | 0.8226 | 7.321 | 1/1.024 | ||
1.192 | 7.434 | 7/0.390 | |||||||
1.178 | 7.280 | 16/0.254 | |||||||
1.212 | 7.540 | 34/0.180 | |||||||
1.163 | 7.160 | 41/0.160 | |||||||
20 | 30 | 0.8118 | 1.021 | 0.0008019 | 0.5174 | 4.60 | 1/0.813 | ||
0.9600 | 4.70 | 7/0.310 | |||||||
0.9421 | 4.65 | 21/0.180 | |||||||
0.9305 | 4.54 | 26/0.160 | |||||||
22 | 25.35 | 0.6439 | 624.6 | 0.0005047 | 0.3256 | 2.895 | 1/0.645 | ||
0.7650 | 3.186 | 7/0.254 | |||||||
0.7524 | 2.970 | 17/0.160 | |||||||
24 | 20.1 | 0.5106 | 404 | 0.0003173 | 0.2047 | 1.820 | 1/0.511 | ||
0.6000 | 1.060 | 7/0.200 | |||||||
0.60525 | 1.920 | 11/0.160 | |||||||
26 | 15.94 | 0.40490 | 254.1 | 0.0001996 | 0.1288 | 1.145 | 1/0.404 | ||
0.47400 | 1.223 | 7/0.160 | |||||||
28 | 12.64 | 0.32110 | 159.8 | 0.0001255 | 0.08097 | 0.7198 | 1/0.322 | ||
0.38100 | 0.7903 | 7/0.127 | |||||||
30 | 10.03 | 0.25480 | 100.6 | 0.0007901 | 0.05097 | 0.4531 | 1/0.254 | ||
0.30000 | 0.4900 | 7/0.100 | |||||||
32 | 7.950 | 0. 2091 0 | 63.20 | 0.00004964 | 0.03203 | 0.2847 | 7/0.080 | ||
34 | 6.305 | 0.16010 | 39.75 | 0.00003122 | 0.0 2014 | 0.1790 | 1/0.161 | ||
36 | 5 | 0.12700 | 25 | 0.00001963 | 0.01267 | 0.1126 | 1/0.128 | ||
38 | 3.965 | 0. 1007 | 15.72 | 0.00001235 | 0.007968 | 0.07084 | 1/0.102 | ||
40 | 3.145 | 0.07987 | 9.891 | 0.000007768 | 0.00 2012 | 0.04456 | 1/0.080 |