Voltage Drop Tool
Check whether a long landscape lighting run is likely to fade out at the far end
This is a fast planning tool for homeowners. Plug in the load, the one-way distance, and the wire gauge to see how much voltage you may lose before it reaches the last fixtures.
Use It For
Long walkway runs, large front yards, and zones where dim fixtures are a concern.
Best Pairing
Use it alongside the transformer planner so load, cable, and zone layout all stay in sync.
What It Tells You
Estimated current, voltage drop, and a practical note about whether the run still looks safe.
Interactive Calculator
Check voltage drop before you buy cable
Enter the transformer voltage, approximate fixture load, run length, and cable gauge to see how much voltage is likely to disappear on the wire.
Estimated current
5.00 A
Circuit length
160 ft
Voltage drop
1.27 V
Drop percent
10.6%
Result
Estimated fixture voltage
10.73 V
Voltage drop is likely high enough to create uneven performance. Split the run, reduce load, or step up wire size.
How To Read It
- Lower drop percentages usually mean more even brightness across the run.
- If the drop looks high, shorten the run, split the load, or move to a heavier cable.
- Use this as a planning screen, then confirm final layout assumptions before purchase.
Practical note
This tool estimates electrical loss for planning purposes. Fixture sensitivity, tap settings, and final branching layout still matter, so treat this as homeowner guidance rather than final electrical design.