The American wire gauge (AWG), also known as the Brown & Sharpe wire gauge, is a standardized system for defining the diameter of conductive wires.
The table below is a guide only and there are many factors such as alloy composition, ambient temperature and airflow which come into play.
| Gauge | Diameter | Resistance | Max Current | |||
| per 1000 ft | per km | In Air | In Jacket | |||
| OOOO | 0.4600" | 11.6840mm | 0.05Ω | 0.16Ω | 380A | 302A |
| OOO | 0.4096" | 10.4038mm | 0.06Ω | 0.20Ω | 328A | 239A |
| OO | 0.3648" | 9.2659mm | 0.08Ω | 0.26Ω | 283A | 190A |
| 0 | 0.3249" | 8.2525mm | 0.10Ω | 0.32Ω | 245A | 150A |
| 1 | 0.2893" | 7.3482mm | 0.12Ω | 0.41Ω | 211A | 119A |
| 2 | 0.2576" | 6.5430mm | 0.16Ω | 0.51Ω | 181A | 94A |
| 3 | 0.2294" | 5.8268mm | 0.20Ω | 0.65Ω | 158A | 75A |
| 4 | 0.2043" | 5.1892mm | 0.25Ω | 0.82Ω | 135A | 60A |
| 5 | 0.1819" | 4.6203mm | 0.31Ω | 1.03Ω | 118A | 47A |
| 6 | 0.1620" | 4.1148mm | 0.40Ω | 1.30Ω | 101A | 37A |
| 7 | 0.1443" | 3.6652mm | 0.50Ω | 1.63Ω | 89A | 30A |
| 8 | 0.1285" | 3.2639mm | 0.63Ω | 2.06Ω | 73A | 24A |
| 9 | 0.1144" | 2.9058mm | 0.79Ω | 2.60Ω | 64A | 19A |
| 10 | 0.1019" | 2.5883mm | 1.00Ω | 3.28Ω | 55A | 15A |
| 11 | 0.0907" | 2.3038mm | 1.26Ω | 4.13Ω | 47A | 12A |
| 12 | 0.0808" | 2.0523mm | 1.59Ω | 5.21Ω | 41A | 9.3A |
| 13 | 0.0720" | 1.8288mm | 2.00Ω | 6.57Ω | 35A | 7.4A |
| 14 | 0.0641" | 1.6281mm | 2.53Ω | 8.28Ω | 32A | 5.9A |
| 15 | 0.0571" | 1.4503mm | 3.18Ω | 10.44Ω | 28A | 4.7A |
| 16 | 0.0508" | 1.2903mm | 4.02Ω | 13.17Ω | 22A | 3.7A |
| 17 | 0.0453" | 1.1506mm | 5.06Ω | 16.61Ω | 19A | 2.9A |
| 18 | 0.0403" | 1.0236mm | 6.39Ω | 20.94Ω | 16A | 2.3A |
| 19 | 0.0359" | 0.9119mm | 8.05Ω | 26.41Ω | 14A | 1.8A |
| 20 | 0.0320" | 0.8128mm | 10.15Ω | 33.29Ω | 11A | 1.5A |
| 21 | 0.0285" | 0.7239mm | 12.80Ω | 41.98Ω | 9A | 1.2A |
| 22 | 0.0254" | 0.6452mm | 16.14Ω | 52.94Ω | 7A | 0.92A |
| 23 | 0.0226" | 0.5740mm | 20.36Ω | 66.78Ω | 4.7A | 0.729A |
| 24 | 0.0201" | 0.5105mm | 25.67Ω | 84.20Ω | 3.5A | 0.577A |
| 25 | 0.0179" | 0.4547mm | 32.37Ω | 106.17Ω | 2.7A | 0.457A |
| 26 | 0.0159" | 0.4039mm | 40.81Ω | 133.86Ω | 2.2A | 0.361A |
| 27 | 0.0142" | 0.3607mm | 51.47Ω | 168.82Ω | 1.7A | 0.288A |
| 28 | 0.0126" | 0.3200mm | 64.90Ω | 212.87Ω | 1.4A | 0.226A |
| 29 | 0.0113" | 0.2870mm | 81.83Ω | 268.40Ω | 1.2A | 0.182A |
| 30 | 0.0100" | 0.2540mm | 103.20Ω | 338.50Ω | 0.86A | 0.142A |
| 31 | 0.0089" | 0.2261mm | 130.10Ω | 426.73Ω | 0.7A | 0.113A |
| 32 | 0.0080" | 0.2032mm | 164.10Ω | 538.25Ω | 0.53A | 0.091A |
| 33 | 0.0071" | 0.1803mm | 206.90Ω | 678.63Ω | 0.43A | 0.072A |
| 34 | 0.0063" | 0.1600mm | 260.90Ω | 855.75Ω | 0.33A | 0.056A |
| 35 | 0.0056" | 0.1422mm | 329.00Ω | 1079.12Ω | 0.27A | 0.044A |
| 36 | 0.0050" | 0.1270mm | 414.80Ω | 1360.00Ω | 0.21A | 0.035A |
| 37 | 0.0045" | 0.1143mm | 523.10Ω | 1715.00Ω | 0.17A | 0.0289A |
| 38 | 0.0040" | 0.1016mm | 659.60Ω | 2163.00Ω | 0.13A | 0.0228A |
| 39 | 0.0035" | 0.0889mm | 831.80Ω | 2728.00Ω | 0.11A | 0.0175A |
| 40 | 0.0031" | 0.0787mm | 1049.00Ω | 3440.00Ω | 0.09A | 0.0137A |