Wire Gauge Calculator

Find the correct wire size for your campervan's 12V electrical system.

Load Current

amps

One-Way Wire Length

metres

Enter the one-way wire length — the calculator accounts for the return path.
Acceptable voltage drop is 3% (0.36V on a 12V system). Sizes that exceed this are marked as fail.
Based on copper wire with a resistivity of 0.0171 Ω·mm²/m.

Created by Mike Hudson · VandogTraveller.com