Generator Size Calculator
Plan backup power for load shedding. Tick the appliances you will run at the same time, set quantities, and get a recommended generator size in kVA.
| Use | Appliance | Watts | Quantity |
|---|---|---|---|
| Ceiling Fan | 75 W | ||
| LED Bulb | 12 W | ||
| Energy Saver | 25 W | ||
| Refrigerator (Fridge) | 150 W | ||
| TV | 100 W | ||
| Laptop | 65 W | ||
| Water Motor (Pump) | 750 W | ||
| AC 1 Ton | 1200 W | ||
| AC 1.5 Ton | 1800 W | ||
| Washing Machine | 500 W | ||
| Iron | 1000 W |
- Tick the appliances you plan to run at the same time during load shedding.
- Set the quantity for each, or add a custom appliance with its wattage.
- Press Calculate Generator Size to see total watts and the recommended kVA.
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Frequently Asked Questions (FAQ)
How is the recommended kVA size calculated?
The tool adds up the running watts of every appliance you selected, adds 25 percent headroom, then divides by a 0.8 power factor and converts to kVA. The result is rounded up to the nearest standard size: 2.5, 5, 6.5, 8 or 10 kVA.
What is the 25 percent safety headroom for?
The 25 percent headroom covers small voltage drops, motor startup surges and any extra load you may add later, so the generator does not run at its absolute limit.
Does this calculator include starting watts for motors?
It uses running watts plus 25 percent headroom, which covers the startup surge of most home appliances. Large motors like water pumps and AC compressors can spike higher, so avoid starting two of them at the same moment, or choose one size up.
Which appliances should I include in the list?
Include only the appliances that will run at the same time during load shedding. Set the quantity to 0 for items you will not run together, and use the custom row for anything not listed.
Is this generator size calculator free to use?
Yes. It is completely free and runs entirely in your browser. Nothing is uploaded or stored.