Electrical Circuit Planner: Wire Size and Voltage Drop
Prepare one circuit and open wire ampacity and voltage-drop calculators with shared inputs. Compare cable options and create a reusable plan link.
Choose a cable conversion or conductor calculator according to the question you need to answer. An AWG-to-mm² conversion compares cross-sectional area; it does not establish the current a cable may carry. For current capacity, use a wire ampacity calculation with the conductor material, insulation rating, terminal temperature limits and installation conditions. For a long cable run, check voltage drop separately using current, route length and resistance or impedance. Keep one-way route length distinct from the complete outgoing-and-return path: each calculator explains which value it expects. Copper and aluminium with the same area do not have identical resistance. Use the tools listed below to compare units and planning assumptions, then check the equipment documentation and the installation requirements that apply to your project.
Start your cable calculation
Follow the part of the workflow that matches the information you have.
Convert mm², AWG and kcmil — Compare cross-sectional areas before choosing the input units in a calculator.
Wire size by ampacity — Check load current and the stated installation assumptions.
Compare AWG/kcmil voltage drop — See how conductor size changes drop at the same load and distance.
Voltage drop from area and current — Check route length, material and operating temperature.
Three-phase cable impedance — Work with your cable resistance and reactance data.
Convert MCM / kcmil to mm² — Convert in either direction, check circular mils and download the 18-size area table. Area conversion does not establish ampacity.
Prepare one circuit and open wire ampacity and voltage-drop calculators with shared inputs. Compare cable options and create a reusable plan link.
Quickly estimate line losses and ensure your circuits run efficiently with our instant voltage drop calculator for 1‑phase and 3‑phase systems, Cu/Al conductors, and AWG/kcmil sizing (Volts & %). Save time and avoid costly mistakes with clear results in volts and percent.
Estimate wire size from load current, ampacity, insulation and terminal ratings, ambient temperature and conductor count. Copper and aluminum supported.
Convert mm² to AWG and compare wire areas, diameters and kcmil sizes. Includes a conversion table and separate ampacity and voltage drop checks.
Calculate short-circuit current in cables quickly and accurately with our IEC-compliant Short-Circuit Current Calculator. Easy, reliable, and precise results.