Voltage Drop Calculator

Calculate voltage drop in wires based on current, length, and material.

Calculate Drop

Calculate voltage drop and wire efficiency

What is Voltage Drop Calculator?

A voltage drop calculator determines the loss of voltage in a circuit due to the resistance of the wires. Excessive voltage drop can cause equipment to fail or work inefficiently.

How to Use Voltage Drop Calculator?

Enter the source voltage, current load, wire length, and select the wire size and material. The calculator will show the voltage drop and percentage loss.

Voltage Drop Calculator Accuracy

Calculations are based on standard resistivity values for copper and aluminum at 20°C (68°F). Actual drop may vary with temperature and installation method.

Frequently Asked Questions

A 3% voltage drop is the maximum recommended for residential branch circuits. For main service feeders, a 5% drop is generally acceptable according to electrical standards.