Electricity Bill Calculator

Estimate your monthly bill from appliance wattage and usage hours.

Overview

Estimates monthly electrical consumption and power bill costs from appliance wattage, daily usage hours, and municipal tiered tariff slabs.

Formula & Calculation Method

Monthly Units (kWh) = [Appliance Wattage (W) × Daily Hours × 30 Days] / 1,000 | Bill = kWh × Tariff Rate per Unit

1 electricity billing unit equals 1 kilowatt-hour (kWh). Tiered tariff slabs charge progressively higher rates as consumption crosses unit thresholds.

Worked Example: 1.5-Ton Inverter AC (1,500W) Running 8 Hours Daily at ₹8/Unit

Inputs: Wattage = 1,500 Watts | Daily Usage = 8 Hours | Rate = ₹8.00 per kWh Unit

  • Daily energy consumption = (1,500 × 8) / 1,000 = 12.0 kWh units/day
  • Monthly energy consumption = 12.0 × 30 days = 360 kWh units/month
  • Monthly electricity cost = 360 units × ₹8.00 = ₹2,880 per month

Summary: Power = 1,500 W | Monthly Units = 360 kWh | Monthly Operating Cost = ₹2,880

Common Use Cases

  • Appliance Running Cost Audit: Calculate exactly how much money running an air conditioner, gaming PC, or space heater costs per month.
  • Energy Efficiency Comparison: Compare operating costs of 5-star BEE rated inverter appliances against older non-inverter models.
  • Solar Panel Sizing: Determine monthly kilowatt-hour household demand to properly size rooftop solar net-metering systems.

Frequently Asked Questions

What is 1 unit of electricity on an electricity meter?

1 unit of electricity equals 1 kilowatt-hour (kWh), which is 1,000 watts of power consumed continuously for 1 hour.

How much power does a refrigerator use per day?

A modern 3-star to 5-star frost-free refrigerator consumes approximately 0.8 to 1.5 units (kWh) per day.

What is the difference between an inverter AC and a regular AC?

Inverter ACs regulate compressor motor speed continuously, saving 30% to 50% electricity compared to regular on/off compressor models.

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