Electricity cost calculator
Calculate kWh usage and daily, monthly, and yearly electricity cost from device wattage, runtime, and your kWh price.
Power (W)
Hours per day
Days
Price per kWh
Result
Energy used: 135 kWh
Daily cost: 0.68
Monthly cost (30 days): 20.25
Yearly cost (365 days): 246.37
How to use
1. Enter device power in watts.
2. Set hours per day and billing period in days.
3. Enter your electricity price per kWh.
4. Read consumption and cost breakdown.
Example
Electricity cost calculator
Calculate kWh usage and daily, monthly, and yearly electricity cost from device wattage, runtime, and your kWh price.
When to use
• When you need a quick estimate without spreadsheets.
• When you want privacy — calculations stay on your device.
Limitations
• When you need certified engineering or legal calculations.
• When site-specific conditions require a professional survey.
About this calculator
Calculate kWh usage and daily, monthly, and yearly electricity cost from device wattage, runtime, and your kWh price.
Frequently asked questions
Is my data uploaded?
No. All math runs locally in your browser.
Is this tool free?
Yes. No account or subscription required.