Hardware tool
Voltage Drop Calculator
Calculate voltage loss, drop percentage, load voltage, and wire power loss.
Runs in your browserResult
- Voltage drop
- 4.764 V
- Drop percentage
- 3.97%
- Voltage at load
- 115.236 V
- Wire power loss
- 95.28 W
- Loop resistance
- 0.2382 Ω
Uses approximate copper resistance at room temperature. Verify conductor ampacity, operating temperature, circuit topology, code, and equipment requirements.
How to use this voltage drop calculator
- Enter the known electrical values with the correct units, then check the proposed current, voltage, resistance, or wire result.
- Review the calculated totals, units, and assumptions. Check the inputs and units before relying on the result.
- Change one input at a time to compare another case, then copy or save the result you plan to use.
About this voltage drop calculator
Voltage Drop Calculator helps you calculate voltage loss, drop percentage, load voltage, and wire power loss. The input and result appear together for easy comparison.
You can also use it to compare results after changing one input.
Example
Compare wire gauges for the same current and distance to see how resistance changes voltage at the load and power lost in the cable.
Common uses
- → calculate voltage loss, drop percentage, load voltage, and wire power loss
- → compare results after changing one input
- → save an estimate for planning or comparison