Energy Consumption Calculator
Calculate how many kWh an appliance uses per day, month, or year from its wattage and run time.
How it works
- 1Enter the appliance power rating in watts (from the label or manual).
- 2Enter the hours used per day and the number of days in your period.
- 3The calculator uses kWh = watts × hours ÷ 1000, then scales to the period.
Use cases
- Estimating the monthly draw of a fridge, washing machine, or air conditioner.
- Comparing the running energy of two appliances before buying.
- Planning a solar or battery system by knowing your daily kWh load.
Frequently asked questions
What is a kilowatt-hour (kWh)?
A kWh is the energy of a 1000 W device running for one hour: kWh = watts × hours ÷ 1000. A 100 W bulb for 5 hours uses 0.5 kWh.
How do I find an appliance’s wattage?
Check the rating label or manual. For devices that cycle on and off, like fridges, use the average wattage rather than the peak.
How do I turn kWh into a bill cost?
Multiply the kWh by your tariff per kWh. Pair this with the Electricity Cost Calculator for a direct cost estimate.
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