Enter an AWG size (for example 12 or 4/0) to see its cross-section in mm² and its diameter, or enter mm² to find the equivalent gauge.
| AWG | Diameter (mm) | Diameter (in) | Area (mm²) |
|---|---|---|---|
| 4/0 AWG | 11.684 | 0.46 | 107.219 |
| 3/0 AWG | 10.405 | 0.4096 | 85.029 |
| 2/0 AWG | 9.266 | 0.3648 | 67.431 |
| 1/0 AWG | 8.251 | 0.3249 | 53.475 |
| 1 AWG | 7.348 | 0.2893 | 42.408 |
| 2 AWG | 6.544 | 0.2576 | 33.631 |
| 4 AWG | 5.189 | 0.2043 | 21.151 |
| 6 AWG | 4.115 | 0.162 | 13.302 |
| 8 AWG | 3.264 | 0.1285 | 8.366 |
| 10 AWG | 2.588 | 0.1019 | 5.261 |
| 12 AWG | 2.053 | 0.0808 | 3.309 |
| 14 AWG | 1.628 | 0.0641 | 2.081 |
| 16 AWG | 1.291 | 0.0508 | 1.309 |
| 18 AWG | 1.024 | 0.0403 | 0.823 |
| 20 AWG | 0.812 | 0.032 | 0.518 |
| 22 AWG | 0.644 | 0.0253 | 0.326 |
| 24 AWG | 0.511 | 0.0201 | 0.205 |
Note: this converts sizes only. The current a wire can safely carry (ampacity) depends on insulation, temperature, installation method and local code (for example the NEC in the US) – check the applicable tables before choosing a wire.
AWG is defined by a formula: diameter (in) = 0.005 × 92^((36 − n) ÷ 39). A smaller number means a thicker wire, and every 3 gauges roughly halve or double the cross-section. Sizes thicker than 0 AWG are written 1/0 to 4/0.
Metric cables come in standard sizes such as 1.5, 2.5 and 4 mm², which fall between AWG sizes. When replacing a wire, choose the size that is not smaller than the required cross-section.
12 AWG is 3.31 mm², with a diameter of 2.05 mm (0.081 in).
2.5 mm² is about 13.2 AWG. Its closest common building-wire size that is not smaller is 12 AWG.
14 AWG is 2.08 mm² and 10 AWG is 5.26 mm².