StandbyHomePower.com — Real Power. Brighter Tomorrows.

Calculate Your Generator Size 

What do you want to keep running during an outage?

Essentials: keep the basics running — refrigerator, a few lights, Wi-Fi and internet, phone charging, critical medical device. Lower power need. Best when you mainly want safety and essentials.Comfort: keep more of your daily routine going — refrigerator, more lights, Wi-Fi, TV, microwave, garage door opener, home office. Medium power need. Best when you want the house to feel mostly normal.High Demand: support larger loads — central AC, well pump, electric water heater, dryer or range, EV charger, more of the home. Higher power need. Best when you want to power major equipment too.

Choose what you want to power below — the calculator estimates the generator size that setup may need.

Appliances & home systems

Refrigerator200 W running
Freezer200 W running
Lights (10 LED bulbs)100 W running
Wi-Fi20 W running
TV100 W running
Microwave1,500 W running
Garage door opener500 W running
Furnace blower800 W running
Sump pump1,000 W running
Well pump1,500 W running
Window AC1,200 W running
Central AC3,500 W running
Electric water heater4,500 W running
Medical equipment400 W running
Computer200 W running
Washer500 W running
Electric dryer5,000 W running
Dishwasher1,500 W running

Running watts

Power needed while equipment is operating.

Starting watts

Extra power some equipment needs when starting.

Essential vs whole-home

Backing up fewer circuits usually requires less generator capacity.

Want to understand cost too?

Understand Costs