VDrop vs Wire Gauge & Size Calculator

600V and less voltage drop calculator. Outputs provide the user details from the calculations to allow users to perform due diligence and develop confidence in the results. Custom voltages may be inputted (600V and less) also.

Wire Gauge Calculator Find the minimum safe wire size in seconds. Enter voltage (V), current (A), run length (ft/m), and allowable voltage drop (%) — the app returns the smallest conductor that satisfies both voltage drop and ampacity, and shows you which one set the size. New in this version • IEC (mm²) sizing — now alongside NEC (AWG/kcmil); switch standards in one tap • Ampacity check — sizes by current-carrying capacity, not just voltage drop • More accurate AC — power factor, conductor temperature, and reactance • Continuous load (125%), insulation rating, and installation-method options Features • Results in AWG/kcmil, inch, mm, and sq.mm at a glance • Conductor materials: Copper, Aluminum & Steel • Multiple parallel conductors per phase • DC, AC single-phase, and three-phase (3- & 4-wire) • Quick-pick common supply voltages + shareable results Perfect for • Low-voltage DC — automotive, RV, solar • Residential AC — single-phase 120 V / 230 V • Industrial three-phase — 480 V (US) / 400 V (EU) • Long-distance power runs Always verify results against your local electrical code.