Electrical Contractor Tools

Free Tools Built for Electricians

Stop wrestling with spreadsheets. Our calculators follow NEC standards and give you professional results in minutes — not hours.

Residential Load Calculator

Calculate the total electrical service load for a single residential dwelling unit per NEC Article 220. Enter square footage, appliances, and circuits — get your service size instantly.

  • General lighting & receptacle loads (NEC 220.12)
  • Small appliance and laundry circuits (NEC 220.52)
  • Fixed appliance loads with demand factors
  • HVAC vs electric heat comparison (NEC 220.60)
  • Service size recommendation (100A, 150A, or 200A)
Open Load Calculator

How It Works

1

Enter Your Info

Plug in square footage, appliances, and major loads. The form guides you through each section.

2

We Calculate

Demand factors, derations, and NEC rules are applied automatically. No manual lookups needed.

3

Get Your Results

View your total calculated load and recommended service size. Save it or print for your records.

More Electrical Tools Coming Soon

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