Voltage Drop & Wire Size vs Wire & Load

Voltage Drop & Wire Size brings voltage-drop calculation and wire sizing into one practical workflow. Check a run with the conductor you already have in mind, see the result immediately, and move to a better size when the drop is outside your target. • Check voltage drop with the conductor you want to evaluate • Find the smallest available size that meets your selected target • Send the recommended size back into the calculation The app supports NEC / AWG and BS-style / Metric workflows across DC, single-phase AC, split-phase 120/240, and three-phase AC systems. You can enter load in amps or watts, choose copper or aluminum conductors, and work from preset drop limits or a custom target depending on the job you are checking. • Review voltage drop in volts and percent • See load voltage, running current, power loss, and a next-size-up comparison • Adjust power factor and installation method For NEC-based work, the app also supports ampacity-aware calculations with continuous load, ambient temperature, conductor grouping, and conductor temperature rating inputs. Saved calculations can be reopened later with notes, and ambient temperature can be shown in Celsius or Fahrenheit. • Review adjusted ampacity in NEC mode • Reopen saved calculations and keep notes with the job • Switch ambient temperature display between Celsius and Fahrenheit This app is intended as calculation guidance. Verify final conductor selection, ampacity, and installation requirements against the applicable standard and manufacturer data before use.

Stop guessing the right wire size. Wire & Load is the no-internet-needed reference every electrician and maintenance tech wants in their pocket. GET AN INSTANT RECOMMENDATION for AWG / mm² wire size, voltage drop percentage, and the matching standard circuit breaker — driven by NEC 2023 / 75°C ampacity tables and the 240.6(A) breaker series. WHAT'S INSIDE • Voltage-drop calculator — single- and three-phase, copper or aluminum • Configurable voltage-drop limit (0.5% – 10%) • NEC 240.4(B) next-size-up breaker rule applied automatically • 60°C limits for 14/12/10 AWG copper and 12/10 AWG aluminum pre-applied per NEC 240.4(D) • Continuous-load (≥ 3 hr) 1.25× multiplier toggle • Power-mode input — enter watts and power factor, the app derives the working current OFFLINE REFERENCE TABLES • AWG ↔ mm² ↔ diameter (ASTM B258) • Copper and aluminum ampacity (NEC 310.16, 75°C) • Standard breaker sizes (NEC 240.6(A)) • Motor starting inrush multipliers — DOL, star-delta, soft starter, VFD (NEMA MG-1) DESIGNED FOR THE FIELD • Works on any job site, no signal needed • Search built into every reference table • Both AWG and mm² always shown on results • Switch between metric (mm² / m) and imperial (AWG / ft) • Localized in English, Spanish, Japanese, French, German, and Portuguese PRIVACY FIRST No accounts. No analytics. No ads. No tracking. Your inputs never leave your device. PRICING Try Wire & Load free for 7 days. After that, unlock lifetime access for a single $1.99 purchase — no subscription, no recurring charges, free updates. DISCLAIMER This app provides general reference information based on commonly-used electrical engineering tables and formulas. Results are estimates and do not constitute professional engineering advice. Always follow the electrical code applicable in your jurisdiction and consult a licensed electrician or engineer.