Electricity Cost Calculator

Estimate annual electricity use and costs from device power and usage or a known annual kWh amount, using a price you enter in euro cents per kWh.

Electricity cost estimate

Calculation mode
ct/kWh

Enter euro cents per kWh. Use a decimal point (.) for decimals; grouping separators are not accepted.

Device use

The estimate assumes the entered power during the stated use time. Actual device power can vary.

W

From 0 to 1,000,000 watts; up to four decimal places.

hours/day

From 0 to 24 hours per day; up to four decimal places.

days/week

Whole number from 0 to 7. Enter 0 if the device is not used.

devices

Whole number from 1 to 1,000 devices.

Estimated costs

Results appear when the active fields contain valid values.

What this tool does

Estimate electricity use and costs either from device power and usage or from a known annual consumption. Enter the electricity price yourself in euro cents per kWh.

How to use the tool

  1. Choose device use and enter power in watts, hours per day, days per week and the number of identical devices; enter the shared electricity price in euro cents per kWh.
  2. Choose annual consumption to enter a known kWh-per-year value. Enable the base-price option only if you want to include a known fixed yearly charge.
  3. Results update automatically when all active values are valid. Energy is shown in kWh and costs in EUR.

Useful applications

  • Estimate the cost of regular computer use without relying on a preset power profile.
  • Compare several identical devices by changing the device count.
  • Turn a known annual kWh figure into estimated energy charges.
  • See how operating time or weekly use changes the estimate, or include a tariff's fixed annual charge in consumption mode.

Notes and limitations

  • The device estimate assumes the entered power during the specified use time; real device power can vary.
  • The calculator uses a 365-day year. Average monthly cost is annual cost divided by 12; average daily cost is annual cost divided by 365. These are calendar averages.
  • The electricity price is entered manually; no tariff is selected automatically. Results are estimates, not a guaranteed bill.
  • The annual base price is included only in annual-consumption mode when enabled.
  • Displayed amounts are rounded to two decimal places.

Frequently asked questions

How are device electricity costs calculated?

The calculator uses power in watts, operating hours, days of use per week and the number of devices to estimate annual kWh, then applies your price per kWh.

Can I calculate the cost of multiple identical devices?

Yes. Enter the number of identical devices in device mode; the estimate scales the energy use and cost by that count.

What is the difference between a watt and a kilowatt-hour?

A watt measures power at a point in time. A kilowatt-hour measures energy used over time; the calculator converts power and usage time into annual kWh.

Why might my actual electricity costs differ from the estimate?

A device's power draw and your usage can vary. Your actual tariff may also include price changes or charges that are not entered here.

When should I include the annual base price?

Enable it in annual-consumption mode when you know the tariff's fixed yearly charge and want it included in the annual total.

How are average monthly and daily costs determined?

The calculator divides the annual cost by 12 for a monthly average and by 365 for a daily average. They are calendar averages, not exact costs for a specific month or day.

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