Generator planning calculators
Plan your generator load, site and fuel costs.
Select the major loads you want available during an outage. The tool estimates steady running load only—it does not hide motor-starting surge or model-specific performance behind a made-up multiplier.
Plan the loads
What needs to run during an outage?
Select the loads you expect to run at the same time. Edit the example values using the equipment nameplate or manufacturer data. The optional home-size field is context only; square footage does not enter the calculation.
The starting values are examples, not equipment specifications. Replace them with nameplate or manufacturer data. A zero in “Extra at start” means you have not entered a surge value; it does not confirm that the load has no startup surge.
The important distinction
Running load
The approximate steady electrical demand of the equipment operating at the same time. This is useful for planning, but it is not the whole sizing calculation.
Starting / motor demand
Compressors, pumps and motors can require substantially more power at startup. That event can determine whether a generator that looks large enough on steady watts actually works.
Use the full sizing guide before choosing a generator.
Starting loads
Use actual HVAC/pump nameplate data or manufacturer documentation where possible.
Fuel-specific output
Some dual-fuel models do not produce the same rated output on natural gas and propane.
Load management
A system may delay selected large loads rather than requiring every circuit to start simultaneously.