AWG to mm diameter chart
Values are for the bare conductor, solid copper, not including insulation. The overall cable is larger.
| AWG | Diameter (in) | Diameter (mm) | Area (mm²) | Circular mils |
|---|---|---|---|---|
| 4/0 | 0.4600 | 11.684 | 107.22 | 211,600 |
| 3/0 | 0.4096 | 10.405 | 85.03 | 167,800 |
| 2/0 | 0.3648 | 9.266 | 67.43 | 133,100 |
| 1/0 | 0.3249 | 8.251 | 53.48 | 105,600 |
| 1 | 0.2893 | 7.348 | 42.41 | 83,690 |
| 2 | 0.2576 | 6.544 | 33.63 | 66,360 |
| 3 | 0.2294 | 5.827 | 26.67 | 52,620 |
| 4 | 0.2043 | 5.189 | 21.15 | 41,740 |
| 6 | 0.1620 | 4.115 | 13.30 | 26,240 |
| 8 | 0.1285 | 3.264 | 8.37 | 16,510 |
| 10 | 0.1019 | 2.588 | 5.26 | 10,380 |
| 12 | 0.0808 | 2.053 | 3.31 | 6,530 |
| 14 | 0.0641 | 1.628 | 2.08 | 4,110 |
| 16 | 0.0508 | 1.291 | 1.31 | 2,580 |
| 18 | 0.0403 | 1.024 | 0.82 | 1,620 |
| 20 | 0.0320 | 0.812 | 0.52 | 1,022 |
| 22 | 0.0253 | 0.644 | 0.33 | 642 |
| 24 | 0.0201 | 0.511 | 0.20 | 404 |
| 26 | 0.0159 | 0.405 | 0.13 | 254 |
| 28 | 0.0126 | 0.321 | 0.08 | 160 |
| 30 | 0.0100 | 0.255 | 0.05 | 101 |
Common gauges at a glance
| Gauge | Diameter | Area | Where you see it |
|---|---|---|---|
| 6 AWG | 0.162 in (4.12 mm) | 13.3 mm² | Ranges, sub panels, ground wire for service |
| 8 AWG | 0.128 in (3.26 mm) | 8.4 mm² | Large AC units, EV chargers |
| 10 AWG | 0.102 in (2.59 mm) | 5.3 mm² | Dryers, water heaters |
| 12 AWG | 0.081 in (2.05 mm) | 3.3 mm² | 20 A household circuits |
| 14 AWG | 0.064 in (1.63 mm) | 2.1 mm² | Lighting, 15 A circuits |
| 18 AWG | 0.040 in (1.02 mm) | 0.82 mm² | Thermostat, doorbell, low-voltage |
AWG diameter formula
Diameter (in) = 0.005 × 92(36 − n) ÷ 39
Diameter (mm) = 0.127 × 92(36 − n) ÷ 39
Here n is the gauge number. For the aught sizes, 1/0 counts as 0, 2/0 as −1, 3/0 as −2 and 4/0 as −3. Example: 12 AWG gives 0.127 × 920.615 = 2.05 mm. The area is the circle area, π ÷ 4 × diameter²: 3.31 mm² for 12 AWG.
mm² to AWG conversion
European and international cable is sold by cross-section area. The nearest AWG by area is shown below. The two systems do not line up exactly, and for safety-critical work you should choose the size whose ampacity meets the load rather than only the closest area.
| Metric size | Nearest AWG | AWG area (mm²) |
|---|---|---|
| 0.5 mm² | 20 AWG | 0.52 |
| 0.75 mm² | 18 AWG | 0.82 |
| 1 mm² | 17 AWG | 1.04 |
| 1.5 mm² | 15 AWG | 1.65 |
| 2.5 mm² | 13 AWG | 2.62 |
| 4 mm² | 11 AWG | 4.17 |
| 6 mm² | 9 AWG | 6.63 |
| 10 mm² | 7 AWG | 10.55 |
| 16 mm² | 5 AWG | 16.77 |
| 25 mm² | 3 AWG | 26.67 |
| 35 mm² | 2 AWG | 33.63 |
| 50 mm² | 1/0 | 53.48 |
| 70 mm² | 2/0 | 67.43 |
| 95 mm² | 3/0 | 85.03 |
Need current limits instead of dimensions? Use the wire size calculator, which checks ampacity and voltage drop.
Frequently asked questions
What is the diameter of 6 gauge wire?
0.162 inches or 4.11 mm for solid bare copper, with a cross-section of 13.3 mm².
What is 12 gauge wire in mm?
2.05 mm in diameter, or 3.31 mm² in area.
How many mm² is 10 AWG?
5.26 mm².
Is 2.5 mm² the same as 12 AWG?
Not exactly. 2.5 mm² sits between 14 AWG (2.08 mm²) and 12 AWG (3.31 mm²) and is closest to 13 AWG (2.63 mm²). Check the ampacity of the cable you actually have rather than substituting by name.