Electricity Usage Calculator
Estimate the units (kWh) and cost your appliances use per day and per month.
Runs in your browser — your data never leaves your device.
About the Electricity Usage Calculator
One “unit” on your electricity bill is one kilowatt-hour (kWh). List your appliances with their power in watts, how many you have and how many hours a day they run, to see which ones use the most units.
Add your average price per unit from your bill for a cost estimate. Taxes, fixed charges and slab rates are not included, so your actual bill will differ.
How to use the Electricity Usage Calculator
- Edit the example rows or add your own appliances: watts (on the label or manual), quantity and hours per day.
- Set the number of days and, optionally, your price per unit.
- Click Calculate units.
Formula
kWh per day = watts × quantity × hours ÷ 1,000. Monthly units = daily kWh × days. Cost = units × price per unit.
For appliances with a thermostat (fridge, AC, iron), enter the hours the compressor or heater actually runs — often a third to half of the time they are switched on.
Examples
The example rows — 3 fans of 80 W for 12 hours, 6 LED bulbs of 12 W for 6 hours and a 150 W fridge running 10 hours — use 4.81 units a day and 144.4 units in 30 days. At an example Rs 50 per unit that is about Rs 7,218.
Frequently asked questions
How many watts does an inverter AC use?
A 1.5-ton inverter AC typically draws 500–1,600 W depending on outside temperature and setting. Check the label or the manufacturer's specification.
Why are the units on my bill higher?
Appliances on standby, old wiring, water pumps and the actual running hours add up. Your meter reading is the true figure.