Wire Gauge Converter (AWG & mm²)
Convert AWG (also called B&S) wire sizes to copper cross-section in mm², or mm² to the nearest AWG.
American Wire Gauge (AWG) and Australian B&S sizes use the same numbers. A smaller number means a thicker wire. Metric cable is sized by the copper cross-section in square millimetres (mm²).
1. Which way?
2. Your wire size
3. Results
How it was worked out
Size chart
Copper cross-section and diameter for a solid conductor, worked out from the standard AWG formula. Stranded cable of the same gauge has about the same copper area but a slightly larger diameter.
| AWG / B&S | Area (mm²) | Diameter (mm) |
|---|---|---|
| 4/0 (0000) AWG | 107.2 | 11.68 |
| 3/0 (000) AWG | 85.0 | 10.40 |
| 2/0 (00) AWG | 67.4 | 9.27 |
| 1/0 (0) AWG | 53.5 | 8.25 |
| 1 AWG | 42.4 | 7.35 |
| 2 AWG | 33.6 | 6.54 |
| 3 AWG | 26.7 | 5.83 |
| 4 AWG | 21.2 | 5.19 |
| 5 AWG | 16.8 | 4.62 |
| 6 AWG | 13.3 | 4.12 |
| 7 AWG | 10.5 | 3.66 |
| 8 AWG | 8.37 | 3.26 |
| 9 AWG | 6.63 | 2.91 |
| 10 AWG | 5.26 | 2.59 |
| 11 AWG | 4.17 | 2.30 |
| 12 AWG | 3.31 | 2.05 |
| 13 AWG | 2.62 | 1.83 |
| 14 AWG | 2.08 | 1.63 |
| 15 AWG | 1.65 | 1.45 |
| 16 AWG | 1.31 | 1.29 |
| 17 AWG | 1.04 | 1.15 |
| 18 AWG | 0.82 | 1.02 |
| 19 AWG | 0.65 | 0.91 |
| 20 AWG | 0.52 | 0.81 |
| 21 AWG | 0.41 | 0.72 |
| 22 AWG | 0.33 | 0.64 |
| 23 AWG | 0.26 | 0.57 |
| 24 AWG | 0.2 | 0.51 |
What this does and doesn't tell you
- It converts size only. It doesn't tell you how much current a cable can carry. That depends on the cable type, insulation, length, voltage drop, how it's installed and the fuse protecting it.
- Watch out for "mm" auto cable. In Australia, 12V auto cable is often sold by its overall size, for example "6mm", which can be much less copper than 6mm². Check the copper cross-section in mm² or B&S on the spec sheet.
- Metric cable comes in standard sizes. The result shows the next standard size up, so you're never going smaller than the AWG size.
- 240V AC mains can kill. In Australia, work on household mains wiring must be carried out by a licensed electrician.
- Low-voltage DC systems can still deliver very high current. A short across a battery can cause burns, fire or a battery explosion.
Next steps
Learn how cable size, current and fuses work together in 12V Wiring Basics. To size a 12V cable for a run, use the Cable Size Estimator and Voltage Drop Calculator on Wired For The Wild.
Technical note: This is general educational information, not a substitute for a design calculation, manufacturer instructions or applicable Australian standards. Everything is worked out in your browser. Nothing is saved or sent anywhere.