AWG Wire Gauge Chart
Look up any AWG wire gauge: diameter in mm and inches, cross-sectional area, copper resistance per km, and an approximate current rating, with a to-scale view.
AWG 12 shown to scale (relative to 4/0)
2.053 mm
Diameter
0.0808 in
3.309 mm²
Area
5.21 Ω/km
Resistance
1.59 Ω/1000 ft
41 A
Approx. ampacity
| AWG | Ø mm | Ø in | Area mm² | Ω/km | Amps* |
|---|---|---|---|---|---|
| 4/0 | 11.684 | 0.46 | 107.219 | 0.16 | 380 |
| 2/0 | 9.266 | 0.3648 | 67.431 | 0.26 | 283 |
| 1/0 | 8.251 | 0.3249 | 53.475 | 0.32 | 245 |
| 2 | 6.544 | 0.2576 | 33.631 | 0.51 | 181 |
| 4 | 5.189 | 0.2043 | 21.151 | 0.82 | 135 |
| 6 | 4.115 | 0.162 | 13.302 | 1.3 | 101 |
| 8 | 3.264 | 0.1285 | 8.366 | 2.06 | 73 |
| 10 | 2.588 | 0.1019 | 5.261 | 3.28 | 55 |
| 12 | 2.053 | 0.0808 | 3.309 | 5.21 | 41 |
| 14 | 1.628 | 0.0641 | 2.081 | 8.28 | 32 |
| 16 | 1.291 | 0.0508 | 1.309 | 13.17 | 22 |
| 18 | 1.024 | 0.0403 | 0.823 | 20.95 | 16 |
| 20 | 0.812 | 0.032 | 0.518 | 33.31 | 11 |
| 22 | 0.644 | 0.0253 | 0.326 | 52.96 | 7 |
| 24 | 0.511 | 0.0201 | 0.205 | 84.21 | 3.5 |
| 26 | 0.405 | 0.0159 | 0.129 | 133.9 | 2.2 |
| 28 | 0.321 | 0.0126 | 0.081 | 212.9 | 1.4 |
| 30 | 0.255 | 0.01 | 0.051 | 338.53 | 0.86 |
*Approximate single-conductor chassis-wiring guide — not a code rating.
Why the numbers run backwards
In American Wire Gauge a bigger number means a thinner wire. The scale comes from manufacturing: gauge counts how many times the wire was drawn through successively smaller dies, so more draws = thinner wire.
It is a geometric scale. Each step is a fixed ratio, captured by one formula: d(mm) = 0.127 · 92^((36 − n) / 39). Two handy consequences: every 6 gauges the diameter roughly doubles, and every 3 gauges the cross-sectional area roughly doubles.
Area, resistance and the “/0” sizes
Cross-sectional area is A = π·d² / 4, and resistance follows R = ρ·L / A (copper ρ ≈ 1.72 × 10⁻⁸ Ω·m). Below AWG 1 the sizes are written 1/0, 2/0, 3/0, 4/0 (“one aught” … “four aught”), continuing the scale to ever-thicker conductors.
About the current rating
Ampacity is not a single number — it depends on insulation temperature rating, whether the wire is bundled or in free air, ambient temperature and acceptable voltage drop. The values here are an approximate single-conductor, chassis-wiring guide for orientation. For mains and building wiring, always follow the applicable code (NEC, IEC) and the insulation's rating.
Typical gauges in the wild
- 22–28 AWG: jumper wires, breadboards, signal and data cables.
- 18–20 AWG: LED strips, low-power DC, hookup wire.
- 14–16 AWG: household lighting and general outlets, speaker runs.
- 10–12 AWG: kitchen/appliance circuits, higher-current DC.
- 2 AWG – 4/0: service entrances, EV chargers, battery and welding cable.