Generator load calculator.
Not sure what size generator you need? Add the appliances and tools you want to run, and we’ll recommend the right Greenfield generator — with headroom for start-up surges.
Build your load
Add what you plan to run at the same time. We account for the higher start-up watts motors draw.
Estimates only — actual draw varies by model and condition. Always check appliance rating plates and leave 20% headroom.
Running vs starting watts.
Running watts
The continuous power an appliance needs once it’s going. We add these up across everything on your list.
Starting watts
Motors (fridges, pumps, compressors) briefly draw much more to start. We add the largest single surge on top.
Headroom
We target ~20% spare capacity so your generator isn’t maxed out — that means quieter running and a longer life.
Found your match?
Explore the full generator range, or talk to our team for help sizing a bigger setup.
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your first order.
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