AWG Wire Gauge Calculator
Convert American Wire Gauge (AWG 0000 to 40) to diameter, cross sectional area in mm² and copper resistance per kilometre, plus voltage drop for a run.
Runs on your device
Result
Results appear here as you type.
What it does
Uses the standard AWG formula d = 0.127 mm × 92^((36 − n)/39) and annealed copper resistivity of 1.724 × 10⁻⁸ Ω·m at 20 °C. Enter a length and current to see the voltage drop over a two wire run.
How to use it
- Enter the gauge (use 0, -1, -2, -3 for 1/0 to 4/0).
- Optionally enter one way length and current.
- Read the dimensions, resistance and drop.
Example
The example fills in realistic values and runs the tool. Select Try an example above to see it.
When it helps
- Choosing wire for 12 V solar or LED projects.
- Converting US specs to mm².
- Estimating voltage drop on long runs.
Questions
Does this tell me the safe current?
No. Ampacity depends on insulation, bundling and ambient temperature. Use your local wiring code tables.
How are 1/0 to 4/0 entered?
1/0 = 0, 2/0 = −1, 3/0 = −2, 4/0 = −3.
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