Electrical Load Calculator

Enter your home's square footage, appliance circuits, and individual loads like electric range, dishwasher, and microwave into the Electrical Load Calculator to find your total calculated load, broken down by general, appliance, and HVAC loads — plus a recommended service size.

sqft

Total living area in square feet. 3VA/sqft as per NEC 2023

circuits

Minimum of 2 circuits required (1500VA each) per NEC

circuits

1500VA each circuit

fans

250VA each fan

VA

Nameplate rating (standard value is 8000VA)

VA

Nameplate rating (standard value is 5000VA)

units

Number of separate heating/cooling systems

VA

VA rating per HVAC unit (typical 3000-6000VA)

Results

Total Calculated Load

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General Load

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Appliance Load

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HVAC Load

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Recommended Service Size

Electrical Load Breakdown

Frequently Asked Questions

How do I calculate electrical load for my home?

Electrical load is calculated by adding up all the electrical demands in your home including general lighting (3VA per sqft), small appliance circuits (1500VA each), major appliances, HVAC systems, and other loads. The total is then used to determine the required electrical service size.

What is the minimum service size for a residential home?

The minimum electrical service size for most modern homes is 100 amps, though many homes today require 200 amp service to accommodate modern electrical loads including electric vehicles, heat pumps, and multiple appliances.

How many small appliance circuits do I need?

The NEC requires a minimum of 2 small appliance circuits for kitchens and dining areas, each rated at 1500VA. Additional circuits may be needed for larger kitchens or homes with extensive counter space.

Do I need to include EV charging in my load calculation?

Yes, if you plan to install an EV charger, it should be included in your load calculation. A typical Level 2 EV charger adds approximately 7200VA (30-40 amps) to your total electrical load.

What voltage amperage (VA) rating should I use for appliances?

Use the nameplate rating found on each appliance. For planning purposes, typical values are: electric range (8000VA), electric dryer (5000VA), dishwasher (1200VA), garbage disposal (900VA), and microwave (1500VA).

How does square footage affect electrical load calculations?

The NEC requires 3VA per square foot for general lighting and receptacle loads. This covers basic lighting, outlets, and general electrical needs throughout the living space of your home.

When do I need a professional electrical load calculation?

You need a professional load calculation when applying for electrical permits, upgrading your electrical service, adding major appliances, or installing EV chargers. Many jurisdictions require calculations stamped by a licensed electrician.

What happens if my calculated load exceeds my current service capacity?

If your calculated load exceeds your current electrical service capacity, you'll need to upgrade your electrical panel and service entrance. This requires a licensed electrician and electrical permits from your local authority.

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