Energy Converters & Calculators
Free tools to convert between watts, kilowatt-hours, amps, BTU, joules, and euros. All calculators use European standards (230V) and real electricity rates.
Power & Energy Conversions
4 tools
Watts to kWh Calculator
Convert watts (W) to kilowatt-hours (kWh) to understand how much energy an appliance uses over time.
Formula: kWh = (Watts / 1,000) x Hours
kWh to Watts Calculator
Convert kilowatt-hours (kWh) back to watts (W) to determine the power draw of an appliance from its energy usage.
Formula: Watts = (kWh / Hours) x 1,000
Amps to Watts Calculator
Convert amperes (A) to watts (W) using the standard European voltage of 230V or any custom voltage.
Formula: Watts = Amps x Volts
Watts to Amps Calculator
Convert watts (W) to amperes (A) to check if your circuit can handle a specific appliance.
Formula: Amps = Watts / Volts
Cost Calculators
3 tools
kWh to EUR Calculator
Convert energy consumption in kWh to cost in euros using real electricity rates from 19 EU countries.
Formula: Cost (EUR) = kWh x Rate (EUR/kWh)
Electricity Cost Calculator
Calculate the daily electricity cost of any device by entering its wattage, usage hours, and your rate.
Formula: Daily Cost = (Watts / 1,000) x Hours x Rate
Annual Electricity Cost Calculator
Calculate the yearly electricity cost of any device based on wattage, daily usage, and your rate.
Formula: Annual Cost = (Watts / 1,000) x Hours/Day x 365.25 x Rate
Unit Conversions
3 tools
BTU to kWh Calculator
Convert British Thermal Units (BTU) to kilowatt-hours (kWh) for heating and cooling calculations.
Formula: kWh = BTU x 0.00029307107
kWh to BTU Calculator
Convert kilowatt-hours (kWh) to British Thermal Units (BTU) for international equipment comparisons.
Formula: BTU = kWh x 3,412.14
Joules to kWh Calculator
Convert joules (J) or megajoules (MJ) to kilowatt-hours (kWh) for scientific and engineering applications.
Formula: kWh = Joules / 3,600,000
About Our Energy Conversion Tools
Energy units can be confusing. Watts, kilowatt-hours, amps, volts, BTU, and joules all measure different aspects of electrical energy, and knowing how to convert between them is essential for understanding your electricity usage and costs. Our conversion tools make these calculations simple and instant.
All our calculators use European electrical standards by default. The standard household voltage in Europe is 230V (compared to 120V in North America), and all amp-to-watt conversions reflect this. For cost calculations, we use real electricity rates from 19 EU countries, giving you accurate cost estimates based on where you live.
Whether you need to figure out if your circuit breaker can handle a new appliance, calculate how much energy your devices use, estimate your electricity costs, or convert between international energy units for heating and cooling comparisons, these tools have you covered. Every conversion updates instantly as you change the inputs, and each tool includes a detailed formula explanation so you understand exactly how the calculation works.