All Energy Units

How to Convert Energy Units?

Energy conversion allows you to translate measurements of work, heat, or power capacity between different unit systems. Energy is the capacity to do work and exists in many forms including kinetic, potential, thermal, electrical, and chemical. Different fields use various energy units, making conversion essential for scientific research, engineering, and everyday applications.

The key conversion factors are:
- 1 kJ = 1,000 J = 0.239 kcal
- 1 kcal = 4,184 J = 4.184 kJ
- 1 kWh = 3,600,000 J = 3,600 kJ
- 1 BTU = 1,055.06 J = 0.252 kcal

Units

Joule (J)

The joule is the SI unit of energy, named after English physicist James Prescott Joule. One joule equals the work done when a force of one newton moves an object one meter. It is the standard unit in physics and engineering for measuring energy, work, and heat. Kilojoules (kJ) and megajoules (MJ) are commonly used for larger quantities.

Calorie (cal) and Kilocalorie (kcal)

A calorie is the amount of energy needed to raise the temperature of one gram of water by one degree Celsius. The kilocalorie (kcal), equal to 1,000 calories, is commonly used in nutrition and is often labeled simply as 'Calorie' (with capital C) on food packaging. One kcal equals approximately 4.184 kJ. This unit is widely used in dietary planning and food science.

Watt-hour (Wh) and Kilowatt-hour (kWh)

Watt-hour is a unit of energy equal to one watt of power sustained for one hour. The kilowatt-hour (kWh) is the standard unit for measuring electrical energy consumption and is used by utility companies for billing purposes. One kWh equals 3.6 megajoules (MJ). This unit helps consumers understand their electricity usage and calculate energy costs.

BTU (British Thermal Unit)

BTU is a traditional unit of heat energy commonly used in the United States for heating, cooling, and air conditioning applications. One BTU equals the energy needed to raise the temperature of one pound of water by one degree Fahrenheit. HVAC systems, water heaters, and furnaces are typically rated in BTUs per hour to indicate their heating or cooling capacity.

Electronvolt (eV)

The electronvolt is a unit of energy commonly used in atomic and particle physics. One eV equals the energy gained by an electron when accelerated through an electric potential difference of one volt. It equals approximately 1.602 x 10^-19 joules. This unit is convenient for describing atomic-scale energy levels, photon energies, and particle physics experiments.

Common Energy Conversions