Calculate what size inverter to backup your refrigerator, wifi, sump pump, freezer, or other devices.
All calcs are estimates. Independently verify before purchase.
Your AC power needs
Knowing your AC power needs is key for selecting the right inverter. WattBuild's calculator lets you list the devices you want to power and then tells you the key stats you need to know, as well as showing which products on the market are compatible.
To get started
Use the Add Device section to begin adding your devices. The calculator will compute the most demanding scenario for your needs, so make sure the devices you choose will all be running at the same time to get the best estimate.
Once added, some devices will let you choose different sizes, for example a small, medium, or large refrigerator, so be sure to choose the one that best matches.
Once you've finished adding devices, look at the compatible device list to see which inverters meet your needs.
