Generator size in kW and kVA from your running loads and the start-up surge of motors.
How this works
Add all running watts, then add the extra start-up surge of the biggest motor (non-inverter AC about 3x, pump about 3x, fridge about 5x running). Recommended = the larger of that peak or running x 1.25. kVA = kW / 0.8.
Questions people ask
How do I use the Generator Size Calculator?
Fill in the fields, starting with “Lights, fans, TV, Wi-Fi”, “1.5 ton ACs” and “AC type”, and change any other options that match your home. The answer, a drawing and practical tips update as you type, and the Copy link button saves your numbers in a link you can share.
Is the Generator Size Calculator free?
Yes. The Generator Size Calculator is free, with no sign-up, and works on phones, tablets and computers. The results are estimates to help you plan, so check with a qualified professional before structural, electrical, gas or plumbing work.