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Electricity Cost Calculator

Calculate what appliances cost to run — per day, month and year.

100% Free No signup Privacy-friendly Calculators
Updated Sep 2026
Per day
Per month
Per year

kWh/day · kWh/year

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How to use Electricity Cost Calculator

  1. Enter the wattage — from the appliance label, or a plug-in power meter for real numbers.
  2. Enter daily usage hours — 24 for always-on devices like fridges and routers.
  3. Enter your rate per kWh — your bill's total ÷ kWh used gives the true all-in rate.
  4. Read daily/monthly/yearly costs — the yearly column is what ranks your energy hogs.

What is Electricity Cost Calculator?

An electricity cost calculator turns an appliance's power draw into money: Cost = watts ÷ 1,000 × hours × price per kWh. A 2,000 W heater running 5 hours daily at $0.17/kWh costs 2 × 5 × 0.17 = $1.70/day — $51/month. The kilowatt-hour is the billing unit: one kWh runs a 100 W device for 10 hours.

The intuition it fixes: cost = power × time, so a big number on the label only matters multiplied by hours. A 2,000 W kettle used 10 minutes a day costs pennies; a 100 W device running around the clock quietly outspends it — duty cycle beats wattage.

About the Electricity Cost Calculator

Enter the appliance's wattage (from its label or a plug-in meter), its daily hours, and your electricity rate, and read the daily, monthly and yearly cost.

The household league table it reveals: heating and cooling dominate (a space heater at 1,500 W × 8 h is ~$60/month; AC similar), then water heating, tumble dryers (~3,000 W per load) and old refrigerators (24/7 duty makes even 150 W add up ~$18/month). The sleepers: always-on electronics — a gaming PC idling, set-top boxes, that second fridge in the garage — where 24/7 turns small watts into real money ($1/year per always-on watt at ~$0.11/kWh; more at higher rates).

Find your rate on the bill (total ÷ kWh used beats the advertised base rate, since it captures fees); typical US rates run $0.12–0.30/kWh by state, European rates often €0.25–0.40. Then audit: measure suspects, multiply, and let the yearly column prioritize what to fix.

Frequently Asked Questions

kW × hours × rate: watts ÷ 1,000, times daily hours, times your per-kWh price. A 60 W fan for 8 h at $0.15: 0.06 × 8 × 0.15 = 7.2 cents/day.
Heating/cooling (30–50% of typical bills), water heating (~15%), then dryers, ovens and old refrigerators. Lighting collapsed as a cost with LEDs — a 9 W LED does what a 60 W bulb did.
At ~$0.12/kWh, each continuous watt costs about $1/year — so a 40 W set-top box + router + standby cluster runs $40+/year, and an idle gaming PC (100–200 W) can exceed $150/year. The 24/7 multiplier is what makes small watts expensive.
Divide your bill's total charge by the kWh consumed — that all-in figure (base + delivery + fees) is the honest rate, often 20–50% above the advertised energy-only price. Time-of-use plans vary it by hour.
Watts measure power (the flow rate); kWh measure energy (the total delivered — what you're billed for). A 1,000 W device running one hour uses exactly 1 kWh. Power is the speedometer; kWh is the odometer.

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