21 AWG wire specifications: 0.7229 mm diameter, 0.4105 mm² area. Resistance, weight, and common uses.
| Diameter | 0.7229 mm · 0.028462" · 28.46 mils |
| Cross-sectional area | 0.4105 mm² · 810 circular mils |
| Resistance (copper, 20°C) | 41.9985 Ω/km · 12.8011 Ω/1000ft |
| Resistance (aluminum, 20°C) | 64.5569 Ω/km · 19.6769 Ω/1000ft |
| Ampacity — copper 60°C | — A |
| Ampacity — copper 75°C | — A |
| Ampacity — copper 90°C | — A |
| Ampacity — aluminum 75°C | — A |
| Weight (copper) | 3.678 kg/km · 2.471 lbs/1000ft |
| Weight (aluminum) | 1.108 kg/km · 0.745 lbs/1000ft |
| Closest metric size | 0.4 mm² |
| Skin depth at 60 Hz | 8.531 mm |
| Type | Temperature | Description |
|---|---|---|
| PVC | 60-105°C | General purpose insulation |
| Teflon (PTFE) | 200°C | High temperature applications |
| Silicone | 200°C | Flexible, high temperature |
| Enamel | 155-220°C | Magnet wire coating |