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Electrical load calculations made easy

Stop using manual spreadsheets. Now introducing an easier way to do residential and commercial electrical load calculations. Use our free tool to get accurate results with an instant PDF report that helps finish inspections and close customers faster.

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Complete accurate load calculations in minutes

Optional or standard method

Choose from either method and complete a load calc with pre-loaded common appliances and their output values

Residential and commercial calculations

Includes options to create both residential and commercial load calculations.

Calculations based on NEC rules

Utilizes default values from the 2023 National Electrical Code, Section 220, including values for EV chargers

Inspector-ready reports

Instantly generates a downloadable PDF printout of your calculation to share with inspectors or customers

Smart property data

Automatically detects location and surfaces property data including building square footage for easier calculations

Automatic demand factors

Detects and applies demand factors based on occupancy type for commercial calculations.

The Kopperfield tool helps with load calculations and avoids common mistakes, such as handling an EV charger in a load calc. I refer Kopperfield’s tool to contractors I work with.

Reina M, City Electrical Inspector

Supporting a variety of load calculation scenarios

Single family homes (standard or optional method)

Accessory dwelling units and additions

Multi dwelling units (i.e., duplex, triplex, quad)

Heat pumps

208V single phase dwellings

All common 3Ø voltages

All NEC-defined occupancy types

Generators and batteries (coming soon)

Load calculator demo

Hear it from a pro

See how Kevin from Bella Electric San Diego uses Kopperfield design tools to save time and close more customers.

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Unlock unlimited load calcs

Our free load calculator is limited to 2 free uses. Get more out of your load calcs when you subscribe to our paid plan.

Unlimited load calcs

Branded templates

Custom default values

Team collaboration

Historic record of all calcs

AI-powered panel photo
processing

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Electrical load calculation in 3 easy steps

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Add property info

Enter the address of the job you’re working on and we’ll pull in the square footage to start the residential or commercial electrical load calculation.

Edit the list of appliances

We’ve pre-loaded a list of common appliances and standard output values. Simply check and adjust them to match what you see on the property.