Electricity Bill Calculator

Understanding electricity cost helps households cut waste, compare appliance upgrades, and validate utility bills. Utility companies charge by the kilowatt-hour (kWh) — the energy consumed when a 1,000-watt load runs for one hour. Multiplying each device's power draw by daily runtime and your local rate reveals which habits and appliances dominate your bill.

Energy consumption and cost formulas:

Daily kWh = (Watts × Hours per day) / 1,000

Daily cost = Daily kWh × Price per kWh

Monthly cost ≈ Daily cost × 30

Where Watts is the device's power draw, Hours per day is how long it runs at that draw, and Price per kWh comes from your utility bill (US averages often $0.12–$0.20; Europe can exceed €0.30).

Many appliances cycle rather than run continuously. Refrigerators average 100–200 W over 24 hours despite higher compressor peaks. Divide annual energy guide kWh by 365 for daily estimates. Space heaters and dryers run at nameplate wattage whenever active — those dominate winter bills.

Worked example: A gaming PC (350 W) runs 6 hours daily; a 55" TV (100 W) runs 4 hours; LED lighting (60 W total) runs 5 hours. PC: 350×6/1000 = 2.1 kWh; TV: 0.4 kWh; lights: 0.3 kWh. Total = 2.8 kWh/day. At $0.16/kWh, daily cost = $0.45, monthly ≈ $13.44, yearly ≈ $163. Adding a 1,500 W space heater 8 hours/day in winter adds 12 kWh ($1.92/day) — more than everything else combined.

Add multiple appliances to build a household profile. Compare LED bulb swaps (10 W vs 60 W incandescent) and use the power calculator when only voltage and current appear on nameplates.