DC Cable Sizing Reference
Wire Gauge Calculator
Size the DC cable between your battery bank and inverter. Enter the system voltage, inverter load, and one-way run length — the tool works out the minimum copper gauge that keeps voltage drop and heating within safe limits.
Inputs
Tighter (1%)
3.0%
Looser (10%)
Calculation covers round-trip conductor length (out and back) using standard copper/aluminum resistivity, then checks the result against typical chassis-wiring ampacity so the cable can also carry the current without overheating. For a permanent installation, confirm the final size against your local electrical code or a qualified electrician.
Recommended gauge
AWG
2
Within limits
Circuit readout
Current draw
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Voltage drop
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Drop percent
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Required ampacity
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Conductor cross-section
Illustrative scale drawing of the recommended conductor, — across, shown against the reference ring for AWG 20 (thinnest common gauge). Strand pattern is representative, not a manufacturer spec.
Reference table — AWG sizes used in this calculation
| AWG | Area (cmil) | Diameter | Typical ampacity |
|---|