ElectricianCalc

ElectricianCalc.com is a free web-based toolset providing NEC-compliant electrical calculators for wire sizing, voltage drop, load calculations, and power system design, built by an electrician for professionals and DIYers.

What is ElectricianCalc?

ElectricianCalc is a collection of over 30 interactive calculators that follow National Electrical Code (NEC) standards. Users input parameters like voltage, current, distance, and material type, and the tool outputs wire gauge, voltage drop percentages, conduit fill percentages, and more. It runs entirely in-browser, requires no software installation, and is maintained by an experienced electrician.

Key Features

• NEC Compliant Calculations – All tools follow NEC 2023 standards for safe installations, including temperature correction factors and voltage drop limits (3% for branch circuits, 5% for feeders).
• Comprehensive Tool Set – Covers wire sizing, voltage drop, load calculation, power factor, conduit fill (per NEC Chapter 9), motor starting, transformer sizing, fault current (in compliance with NEC 110.24), grounding electrode sizing, service entrance, branch circuit, lighting calculation, energy cost, EV charging, whole house load (NEC 220.82), generator sizing, three-phase power (Wye and Delta), capacitor sizing, solar system, emergency system, conduit bending, resistor color code (4/5/6-band), and more.
• Real-time Results – Instant feedback with detailed analysis; all calculations update as inputs change.
• Mobile Ready – Responsive design works on phones, tablets, and desktops for on-the-job use.
• Always Free – No cost, no registration, no hidden limits.

Who is it for?

• Electricians – Use on job sites to quickly determine wire sizes, voltage drop, and conduit fill, ensuring code compliance and avoiding costly mistakes.
• Electrical Engineers – Design power systems, size transformers, and perform fault current analysis using standardized NEC methods.
• Contractors – Prepare accurate bids and permit applications with load calculations and panel schedules.
• Students – Practice electrical calculations and learn NEC requirements through guided tools.

What can you do with ElectricianCalc?

• Size wires for any load – Enter current, distance, and voltage to get the correct AWG/kcmil wire size, considering temperature rating and insulation type (THHN, THWN, XHHW).
• Check voltage drop – Calculate voltage drop on long runs and verify compliance with NEC 3% or 5% limits.
• Perform load calculations – Use the whole house load calculator (NEC 220.82) or individual appliance calculators to determine panel capacity for EV chargers, generators, and service upgrades.
• Estimate energy costs – Calculate running costs for any appliance, compare LED vs incandescent savings, and estimate monthly electric bills.

Pricing

ElectricianCalc is completely free. No premium tiers, no ads, no data collection.

FAQ

Is ElectricianCalc free?

Yes, all calculators are free to use with no registration or payment required.

Do these calculators match code requirements?

Yes, they follow NEC standards exactly, including temperature correction factors and voltage drop limits. Many electricians use them for actual installations.

Can I use these for exam preparation?

They are great for practice, but check your exam rules – most electrical exams require manual calculations.

What voltage systems are supported?

All voltage levels (120V, 240V, 480V, etc.) and both single-phase and three-phase systems are supported.

Are these calculators accurate?

Yes, they use the same formulas as professional electrical software, accounting for all variables that affect real-world installations.