Energy maths, made useful

Know what every watt costs.

Free electricity calculators for households across Europe. Enter your own tariff, see the formula, and get an answer in seconds.

2,000 W heater × 3 h6 kWh
7.4 kW EV charger × 4 h29.6 kWh
1,500 W air fryer × 20 min0.5 kWh
The core formula kWh = watts ÷ 1,000 × hours

A kilowatt-hour measures energy, not power. Once you know kWh, multiply by your electricity price per kWh.

Understand kWh
Then price it Cost = kWh × your unit rate

Because tariffs differ by country, supplier and plan, EuroWattCalc asks for your own rate instead of pretending one price fits everyone.

See a worked example
Country guides

Same maths. Different bills.

Use a country guide to see which number on your bill belongs in the calculator and which fixed charges sit outside the estimate.

Have a wattage and a tariff?

That is enough to get a useful running-cost estimate.

Open calculator →