Choose an example or enter the appliance's exact power rating.
Result
Daily usage1.2 kWh
Daily cost€0.24
Monthly usage36 kWh
Monthly cost€7.20
Yearly usage432 kWh
Yearly cost€86.40
How it works
- Choose an example or enter the appliance wattage.
- Enter its hours and days of operation.
- Add your electricity tariff price.
- Compare daily, monthly and yearly costs.
Practical example
A 300 W PC used 4 hours a day for 30 days consumes 36 kWh per month. At €0.20/kWh it costs €7.20 per month and €86.40 per year.
Formula and explanation
To turn power into energy use, divide watts by 1,000 and multiply by running hours.
Monthly cost = (W ÷ 1,000) × hours per day × days per month × price per kWh.
The yearly result assumes that the same monthly usage continues for twelve months.
Frequently asked questions
Where can I find an appliance's wattage?
Check its label, power adapter, manual or data sheet. A plug-in power meter provides a more accurate figure.
Does it always draw maximum power?
No. Many devices adjust power, enter standby or run in cycles.
Are the example wattages exact?
No, they are starting points. Edit the field to use your appliance's actual rating.