Calculator

Wire Voltage Drop Calculator

By NerdVolt Editorial TeamJune 16, 2026Estimate tool

Accuracy note: The arithmetic on this page is deterministic from your inputs. Solar production, code, utility, incentive, and savings outputs are estimates unless you supply exact equipment specs, tariffs, shade data, and local requirements.

Inputs

Result

How this is calculated

DC/single-phase: voltage drop = 2 × current × resistance per foot × one-way length. Three-phase: voltage drop = √3 × current × resistance per foot × one-way length. Percent = drop ÷ source voltage × 100.

Sources