How to use it
- Enter current, conductor length and the matching length unit.
- Enter resistance per the same unit and system voltage.
- Indicate whether the entered length is one-way, then calculate.
Voltage Drop Calculator
Explore a simplified voltage-drop estimate using an entered conductor resistance.
Important: This calculator is for educational and estimation purposes only. It is not electrical safety, installation, engineering, or code-compliance advice. Always consult a qualified electrician or engineer for real-world electrical work.
About the Voltage Drop Calculator
This estimator applies an entered resistance per meter or foot across a selected circuit length.
How it works
Circuit resistance equals resistance per unit × circuit length. Estimated drop equals current × resistance, and drop percentage compares that result with system voltage.
Example
At 10 A, a 40 m total path with 0.005 Ω per meter has 0.2 Ω resistance and an estimated 2 V drop.
Notes
This is not a conductor-sizing, wiring-design or code-compliance tool. Entered resistance must already match the chosen length unit.