Electrical Load Calculator

Calculate residential electrical service requirements using NEC Standard Method

Project Details
Enter your measurements and requirements

Used to calculate general lighting load (3 VA/sq ft per NEC 220.12)

Kitchen/dining (1500 VA each)

1500 VA each

Appliances & Equipment

12,000W
6,000W
5,000W
1,500W
1,800W
900W
700W
500W

3,500W
4,500W
5,500W
3,500W
4,500W
15,000W
1,500W

Or enter exact nameplate ratings:

Results
Calculated estimates for your project

Total Load

30,100 VA

Total Amperage

125.4 A

Recommended Service Size

150 A

84% of service capacity used

Load Breakdown

Lighting & Receptacles5,625 VA
Cooking Equipment9,600 VA
Electric Dryer5,000 VA
Fixed Appliances6,375 VA
HVAC3,500 VA

Note: This is an estimate based on NEC Standard Method. Actual requirements may vary. Always consult a licensed electrician for service upgrades and permit requirements.

Additional Information

About This Electrical Load Calculator

Our electrical load calculator uses the NEC (National Electrical Code) Standard Method from Article 220 to estimate your home's electrical service requirements. This calculation helps determine whether your current electrical service is adequate or if you need a service upgrade.

The calculator applies proper demand factors as specified in the NEC, including the lighting demand factor table (220.42), cooking equipment calculations (220.55), dryer loads (220.54), and the non-coincident load rule for heating and cooling (220.60). This provides a realistic estimate rather than simply adding up all appliance ratings.

This tool is essential for homeowners planning major additions like EV chargers, hot tubs, or workshop equipment. It helps answer the common question: "Do I need a 200 amp service upgrade?" Understanding your electrical load is the first step in any major electrical project.

How to Use This Calculator

Follow these steps to calculate your electrical load:

  1. Enter your home's total living area in square feet
  2. Confirm the number of small appliance and laundry circuits
  3. Select all electrical appliances and equipment in your home
  4. Add any custom appliances not listed
  5. For HVAC, either select from the list or enter exact nameplate wattages
  6. Review the calculated load and recommended service size
  7. Email yourself the detailed report for contractor discussions
Frequently Asked Questions

Free Electrical Load Calculator - NEC Service Size Estimator | DIYProject.ai