This page covers one aspect of conductor work. For the complete free tool (ampacity, voltage drop, conduit fill, and derating together), use our conductor sizing calculator.

Voltage drop calculator

Run a voltage drop calculator for feeders and branch circuits. Current Systems helps you document Code–consistent voltage drop checks alongside conductor sizing for real-world jobs.

Related: conductor sizing calculator, voltage drop guide, Conductor ampacity calculator.

How this calculator works

Provide circuit length, current, voltage, and conductor details. The app returns expected drop so you can decide if upsizing or shortening runs is justified.

Code alignment

The tool supports electrical design practice for voltage drop review. Always confirm the limits and methods required by your project specification and AHJ.

Combined sizing

Voltage drop often governs wire size on long runs. Use the conductor sizing calculator to see ampacity and drop together.

FAQ

What is a voltage drop calculator?

It estimates voltage drop on feeders and branch circuits using conductor properties and load current so you can compare results to common design limits and document wire sizing decisions.

Does the calculator support copper and aluminum?

Yes. You can model conductor types used in installations and compare outcomes for long runs, high current, or mixed material choices.

Why do electricians care about voltage drop?

Excessive drop can affect motor torque, lighting levels, and sensitive equipment. Documenting expected drop supports code-consistent design and reduces callbacks on longer feeders and branch circuits.