How to Calculate Electricity Bill
Understanding how your electricity bill is calculated helps you identify energy-hungry appliances and reduce your monthly costs.
Electricity Units Formula
Units (kWh) = Power (Watts) × Time (Hours) / 1000
Where:
- kWh = Kilowatt-hours (units of electricity)
- Watts = Power rating of appliance
- Hours = Usage time
Step-by-Step:
- 1
Find wattage
Check appliance label for power rating (watts).
- 2
Estimate daily hours
How many hours per day you use it.
- 3
Calculate monthly units
(Watts × Hours/day × 30) / 1000 = monthly kWh.
- 4
Multiply by tariff
kWh × rate per unit = monthly cost.
Worked Examples:
AC usage
Power: 1500WHours/day: 8Rate: ₹7/unit
Result: ₹2,520/month
Units = 1500 × 8 × 30 / 1000 = 360 kWh. Cost = 360 × 7 = ₹2,520