A planning range only. A licensed installer should run a proper load calculation and check your gas supply before you buy.
Get a Real Load CalculationWhat the calculator counts
It adds a base load for lights, fridge, electronics and outlets scaled to your square footage. Then it adds your AC systems by tonnage, your heat type and your big electric appliances.
For whole-home coverage it assumes load management, which is the standard way installers cover an entire Houston home without oversizing. Results round to common generator sizes.
What changes the answer most
- Number and size of AC systems
- Electric heat strips, which many installers lock out
- Electric water heater, range and dryer
- Pool and well pumps
- EV chargers, often managed or excluded
Want the full picture? Read the sizing guide.
Common questions
Is an online calculator accurate?
It’s a solid planning range, but it doesn’t replace a proper load calculation by a licensed installer, which uses exact nameplate loads, AC starting current and your gas supply.
What size generator for a 2,500 sq ft Houston home?
With two AC systems and gas heat, many homes end up around 20 to 26 kW for whole-home coverage with load management. Electric appliances and pumps can push it higher.
Get ahead of the next outage
Free matching with an independent local installer.