Wire Gauge (AWG) Calculator
Look up AWG wire gauge diameter, cross-section, resistance and ampacity. Free electrical reference tool.
Ampacity columns follow common chassis-wiring and power-transmission practice at 30°C ambient. Always defer to the NEC tables and your local code for permanent installations.
Frequently asked questions
- What does AWG mean?
- American Wire Gauge. Every 3 steps doubles or halves the cross-sectional area; every 6 steps doubles or halves the diameter.
- Chassis vs power transmission ampacity?
- Chassis wiring is single conductors in free air and carries more current. Power transmission is bundled in cable or conduit, where heat builds up, so ratings are lower.
- Does the aluminum factor matter?
- Aluminum has about 1.64× the resistance of copper for the same gauge, which is why it is only used at larger sizes.
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