Welcome to our cable voltage drop calculator! This page operates as both an AC and DC voltage drop calculator and will enable you to calculate the voltage drop across a length of wire using a specified input voltage, rated load current and distance.
Voltage drop due to wires is an important parameter in the design of electrical circuits, especially in high-voltage systems. Controlling and anticipating this voltage drop is essential for building safe and efficient electrical systems.


⬇️ Inputs



R (Ω/km)

X (Ω/km)

⬆️ Outputs

Z (Ω/km)


V_AC_1P (V)

V_AC_3P (V)

💬 We'd love your feedback on this template! It takes 1min


Voltage drop is defined as the amount of voltage reduction in an electrical circuit due to resistance. This resistance can be in the form of electrical components such as resistors, inductors or capacitors, but it can also occur due to the electricity carrying wire's internal resistance.
The voltage drop due to the conductor wire's internal resistance can be calculated as follows:

👀 Read more on calculating impedance using resistance and reactanc

DC circuits

single-phase AC circuits

For three-phase AC circuits


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