How the planner works
SnoutSmart mathArea (acres) = length × width ÷ 43,560. Wireless fences draw a circle: the largest circle that fits inside your yard, centered, has a radius of half the shorter side. GPS fences are compared with the maker's minimum property size, and in-ground systems with the maker's maximum coverage with extra wire.
LimitsReal yards aren't rectangles, and houses, sheds, driveways and slopes change what any system can cover. This is a first check against published ranges, not a guarantee that a system will contain your dog.
SafetyNo electronic fence is a physical barrier. Never rely on one as the only protection near a road.