Energy & Power

Convert energy and power units: joules, kilojoules, calories, kilocalories, BTU, kilowatt-hours, watts, kilowatts and horsepower, including the distinction between metric and mechanical horsepower.

15 free energy & power tools, no signup.

• BTU to Joules ConverterConvert BTU to joules and back. Enter British thermal units and read the energy in joules, kilojoules, or kilowatt-hours.
• BTU to Watts ConverterConvert BTU per hour to watts instantly, and watts back to BTU/h. Based on 1 BTU = 1055.05585262 J.
• Calories to Joules ConverterConvert calories and kilocalories to joules and kilojoules using the exact thermochemical calorie.
• Calories to kJ ConverterConvert Calories (kilocalories) to kilojoules and back, the energy units used on nutrition labels.
• Energy ConverterConvert energy between joules, kilojoules, watt-hours, kilowatt-hours, calories, kilocalories, BTU, foot-pounds, and electronvolts.
• HP to kW ConverterConvert horsepower to kilowatts and back, using mechanical horsepower with metric horsepower available.
• HP to Watts ConverterConvert horsepower to watts instantly, and watts back to horsepower. Based on mechanical horsepower = 745.699872 W.
• Joules to Calories ConverterConvert joules to calories instantly, and calories back to joules. Based on the exact 1 calorie = 4.184 joules definition.
• Kcal to kJ ConverterConvert kilocalories to kilojoules instantly, and kilojoules back to kcal. Based on the exact 1 kcal = 4.184 kJ definition.
• kJ to kcal ConverterConvert kilojoules to kilocalories and back, the two energy units used on food labels around the world.
• kW to HP ConverterConvert kilowatts to horsepower and back, using mechanical horsepower with metric horsepower available.
• kWh to Joules ConverterConvert kilowatt-hours to joules and back. Enter the energy in kWh and read the result in joules, kilojoules, or megajoules.
• Power ConverterConvert power between watts, kilowatts, megawatts, horsepower, metric horsepower, BTU per hour, and foot-pounds per second.
• Watts to Horsepower ConverterConvert watts to horsepower and back. Enter power in watts and read the result in mechanical horsepower or kilowatts.
• Watts to Kilowatts ConverterConvert watts to kilowatts and back. Enter power in watts and read the result in kilowatts or megawatts.