Free · Everyday · Electrical

Voltage Drop Calculator

Estimate two-conductor copper or aluminum circuit voltage drop from length, current, voltage, and wire area.

  • Checked formula
  • Private in your browser
  • No signup
Calculator inputs

Enter your values

Result

Your calculation

Voltage drop
7.46 V
6.22%
Load voltage
112.54 V
Loop resistance
0.4973 Ω

This DC/resistive estimate does not replace electrical-code conductor sizing or professional design.

How to use this calculator

  1. Enter the values and choose the units that match your situation.
  2. Calculate to see the primary answer and useful conversions.
  3. Review the assumptions before using the result for a project or decision.

Private by default

Inputs and results stay in this browser tab. Bookify does not upload or store the values you enter.