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Extension Cord Voltage Drop Calculator
Enter wire gauge, length, load current, and source voltage to calculate voltage drop and percentage.
How to use this tool
- 1Select your wire's AWG gauge.
- 2Enter the one-way length in feet.
- 3Enter the load current in amps.
- 4Enter source voltage.
- 5See voltage drop and percentage.
Frequently asked questions
What voltage drop is considered acceptable?+
3% or less is a commonly cited acceptable threshold for branch circuits — higher drops can cause dimming, overheating, or reduced equipment performance.
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