Energy and Work Converter

Thermodynamic Energy Scales: Electrical, Thermal & Mechanical

Energy is the quantitative property that is transferred to a body or physical system, recognizable in the performance of work and in the form of heat and light.

The Energy Units Across Disciplines

• Joule (J): Base SI unit of work and energy).

• Kilowatt-hour (kWh): Standard utility billing unit for electrical power consumption.

• BTU & Therm: Standard HVAC, boiler, and natural gas utility billing units.

• Kilocalorie: Human nutrition and metabolic energy balance.

• Electronvolt (eV): Quantum physics, semiconductor bandgaps, and particle physics).

How to Use This Calculator

Enter your Energy / Work Value (e.g. 1), From Unit — choose from Joules (J, Base SI), Kilojoules (kJ), Megajoules (MJ), and To Primary Target Unit — choose from Joules (J), Kilojoules (kJ), Megajoules (MJ). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Universal energy conversion factors:1 Kilowatt-hour (kWh) = 3,600,000 Joules = 3.6 MJ = 3,412.142 BTU1 British Thermal Unit (BTU) = 1,055.056 Joules = 252.164 cal = 0.293071 Wh1 Food Calorie (kcal) = 4,184 Joules = 3.96567 BTU1 Foot-Pound (ft·lbf) = 1.355818 Joules1 US Gas Therm = 100,000 BTU = 105.4804 Megajoules (MJ)

Worked Example

For example, converting 1.0 kWh of electrical energy: \, 3,412.14 BTU, 860.42 kcal (food calories), and 2,655,224 ft·lbf.

Understanding Your Result

Unit conversion precision: round to the same number of significant figures as your original measurement. Converting 6 feet to meters gives 1.8288 m — but if your measurement was approximate (±1 inch), expressing more than 2 decimal places is false precision. For international trade and technical specifications, SI units (meters, kilograms, liters) are the standard. US customary units (feet, pounds, gallons) differ from Imperial UK units: 1 US gallon = 3.785 L vs. 1 UK gallon = 4.546 L.