Electric Fence Energizer Calculator
Size output joules from total energized wire, vegetation load, animal pressure, and US or Canada guidance.
Planning estimate only. Use output joules, not stored joules. Install only low-impedance chargers and follow local electrical codes and manufacturer grounding instructions.
Editable multipliers
How energizer size is calculated
Total energized wire is perimeter times hot strands plus interior wire. The US rule uses one output joule per mile of energized wire. The Canada rule uses one joule per 10 km. Animal and vegetation multipliers are editable safety margins.
Sources
US joule-per-mile and grounding guidance: Michigan State Extension. Total electrified-wire load and vegetation warning: University of Maine Extension. Canada joule-per-10-km guidance: OMAFRA pasture production. Voltage targets: Virginia Tech Extension.