Single-phase or DC
Vdrop = 2 I R L
Electrical calculator
Voltage Drop Calculator
Calculate voltage drop and percentage drop for electrical conductors.
Calculator
Enter values
Results update automatically as you type.
Result
About this calculator
How it works
Voltage drop is caused by conductor resistance. Excessive drop can reduce equipment performance and efficiency.
Formulas
Formulas used
Three-phase
Vdrop = sqrt(3) I R L
Percent drop
%drop = Vdrop / Vsupply x 100
Guide
How to use this calculator
- Choose the mode or component type if the calculator provides one.
- Enter known values and select the units beside each input.
- Read the highlighted result first, then use the table for supporting calculated values.
Reference
What the results mean
Voltage drop
The voltage lost along the conductor.
Percent drop
Voltage drop expressed as a fraction of supply voltage.
FAQ
Voltage Drop Calculator questions
Can I use different units?
Yes. Select the unit beside each input. The calculator converts values internally before solving.
Are the results suitable for final design?
Use results for education, screening, and early design checks. Verify final work against standards, datasheets, and project requirements.
Why does the result update automatically?
The calculator listens for input changes and recalculates as soon as enough valid values are available.
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