Voltage Drop Calculator

Estimate copper or aluminum voltage drop for DC, single-phase, or three-phase circuits.

Result

Complete the fields to calculate.

Formula and method

ΔV = k × ρ × L × I / A

Important assumptions

L is one-way length; k accounts for return path or the three-phase factor. Resistivity is an ambient-temperature reference.

Frequently asked questions

Does the calculation run locally?

Yes. Values are processed in your browser and are not sent to a server.

Can I use it for a real installation?

Use it as an educational reference and verify components, tolerances, safety, and applicable code with technical documentation or a qualified person.

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