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Home Generator Size Calculator

Find the minimum wattage generator needed to power your essential home appliances during an outage. Accounts for motor startup surges that can trip or damage undersized generators.

Essential Appliances (watts)

Startup Factor (multiplier)

Fill in the required fields to see your result.

Electrical Home

Home Generator Size Calculator

Determine the right generator size (in kilowatts) to keep your home's essential appliances running during a power outage. Use it when planning an emergency generator purchase or sizing a transfer switch installation.

Essential Lighting (watts)

Refrigeration Load (watts)

Furnace Blower (watts)

Well Pump (watts)

Motor Starting Factor

Fill in the required fields to see your result.

Key differences

	Home Generator Size Calculator	Home Generator Size Calculator
Category	Electrical Home	Electrical Home
Inputs required	2	5
Result	Generator Size Needed (watts)	Recommended Generator Size (kW)
What it does	Find the minimum wattage generator needed to power your essential home appliances during an outage. Accounts for motor startup surges that can trip or damage undersized generators.	Determine the right generator size (in kilowatts) to keep your home's essential appliances running during a power outage. Use it when planning an emergency generator purchase or sizing a transfer switch installation.