AWG wire gauge chart
American Wire Gauge (AWG) sizes for solid copper wire — diameter, cross-sectional area, resistance, and rule-of-thumb current ratings. Lower gauge numbers mean thicker wire. Scan the row for your gauge, or read it in reverse to pick a gauge for a given current.
| Gauge (AWG) | Dia. (mm) | Dia. (in) | Area (mm²) | Resistance (Ω/1000 ft) | Chassis amps | Power amps |
|---|---|---|---|---|---|---|
| 4/0 (0000) | 11.684 | 0.4600 | 107.2 | 0.04901 | 380 | 195 |
| 3/0 (000) | 10.405 | 0.4096 | 85.0 | 0.06180 | 328 | 165 |
| 2/0 (00) | 9.266 | 0.3648 | 67.4 | 0.07793 | 283 | 145 |
| 1/0 (0) | 8.251 | 0.3249 | 53.5 | 0.09827 | 245 | 125 |
| 1 | 7.348 | 0.2893 | 42.4 | 0.1239 | 211 | 110 |
| 2 | 6.544 | 0.2576 | 33.6 | 0.1563 | 181 | 95 |
| 3 | 5.827 | 0.2294 | 26.7 | 0.1970 | 158 | 85 |
| 4 | 5.189 | 0.2043 | 21.2 | 0.2485 | 135 | 70 |
| 6 | 4.115 | 0.1620 | 13.3 | 0.3951 | 101 | 55 |
| 8 | 3.264 | 0.1285 | 8.37 | 0.6282 | 73 | 40 |
| 10 | 2.588 | 0.1019 | 5.26 | 0.9989 | 55 | 30 |
| 12 | 2.053 | 0.0808 | 3.31 | 1.588 | 41 | 20 |
| 14 | 1.628 | 0.0641 | 2.08 | 2.525 | 32 | 15 |
| 16 | 1.291 | 0.0508 | 1.31 | 4.016 | 22 | 10 |
| 18 | 1.024 | 0.0403 | 0.823 | 6.385 | 16 | 7 |
| 20 | 0.812 | 0.0320 | 0.518 | 10.15 | 11 | 5 |
| 22 | 0.644 | 0.0253 | 0.326 | 16.14 | 7 | 3 |
| 24 | 0.511 | 0.0201 | 0.205 | 25.67 | 3.5 | 2.1 |
Values are for solid copper at 20°C. “Chassis amps” is a higher rating for short runs in free air (point-to-point chassis wiring); “Power amps” is a conservative rating for longer power-transmission runs. Real-world ampacity depends on insulation temperature rating, ambient temperature, and bundling — for permanent building wiring, follow NEC 310.16 and local code.
Need to size wire for your run?
This chart is a quick lookup. To size wire from amps, run length, and allowable voltage drop, use the Wire Size Calculator. For 12-volt automotive and marine runs, use the 12V Wire Size Calculator.
How to read this chart
Find your gauge in the first column. The diameter and area columns give the physical size in metric and imperial. Resistance is per 1000 feet of wire — multiply by your run length to estimate total resistance and voltage drop. The two ampacity columns bracket the safe current: use the lower power figure for anything long or enclosed, and the higher chassis figure only for short, well-ventilated runs.
How wire gauge works
AWG is a logarithmic scale: each three-gauge step roughly halves or doubles the cross-sectional area, and every six steps changes the diameter by about half. Thicker wire (a lower gauge number) carries more current with less resistance and less heat. Picking a gauge is a trade-off between current capacity, voltage drop over distance, cost, and flexibility.
AWG chart FAQ
Does a lower gauge number mean thicker wire?
Yes. AWG runs backwards — 10 AWG is much thicker than 20 AWG. The largest common sizes are written 1/0 through 4/0 (pronounced one-aught to four-aught), which are thicker still.
Is this chart for copper or aluminum wire?
These figures are for solid copper. Aluminum has higher resistance and lower ampacity for the same gauge, so size up roughly two gauges when substituting aluminum.
Why are there two ampacity columns?
Current capacity depends on how the wire sheds heat. The chassis column suits short runs in open air; the power column is the conservative choice for long or bundled runs. For permanent wiring, defer to NEC 310.16.