Energy Converter
Energy is a fundamental concept in physics that plays a crucial role in various fields, including engineering, science, and everyday life. It refers to the capacity of a system to do work or produce an effect.
In the context of energy conversion, it is essential to understand different units of energy and their conversion factors. This article aims to provide an educational overview of common energy units and their relationships.

Joule (J): The joule is the SI unit of energy, defined as the amount of work done by a force of one newton moving through a distance of one meter.

Kilojoule (kJ): The kilojoule is a metric unit of energy equal to one thousand joules.
Conversion factor: 1 kJ = 1,000 J 
Megajoule (MJ): The megajoule is a metric unit of energy equal to one million joules.
Conversion factor: 1 MJ = 1,000,000 J 
Wattsecond (Ws): The wattsecond is a unit of energy that is equivalent to 1 joule. It is the energy equivalent to the power of one watt sustained for one second.
Conversion factor: 1 Ws = 1 J 
Watthour (Wh): The watthour is a unit of energy equal to one watt of power consumed for one hour.
Conversion factor: 1 Wh = 3,600 Ws = 3,600 J 
Kilowatthour (kWh): The kilowatthour is a unit of energy commonly used to measure electricity consumption. It represents the energy consumption of a device operating at a power of one kilowatt for one hour.
Conversion factor: 1 kWh = 1,000 Wh = 3,600,000 Ws = 3,600,000 J 
Calorie (cal): The calorie is a unit of energy used commonly around the world. For historical reasons, two main definitions of "calorie" are in wide use. The large calorie, food calorie, or kilogram calorie is defined as the amount of heat needed to raise the temperature of one kilogram of water by one degree Celsius. The small calorie or gram calorie is defined as the amount of heat needed to cause the same increase in one gram of water. Thus, 1 large calorie is equal to 1000 small calories. The calorie unit in this energy converter refers to small calories.
Conversion factor: 1 cal (IT) = 4.186 J; 1 cal (th) = 4.184 J 
Btu (btu): The British Thermal Unit is a unit of energy commonly used in the United States. It is defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit at a constant pressure of one atmospharic unit.
Conversion factor: 1 Btu (IT) = 1,055.06 J; 1 Btu (th) = 1,054.35 J 
Ton (explosives): The ton of explosives is a unit of energy often used in mining and explosives engineering. It refers to the energy release equivalent to one ton of TNT (Trinitrotoluene).
Conversion factor: 1 ton (explosives) = 4.184 GJ (gigajoules) 
Kilogramforce meter (kgf•m): The kilogramforce meter is a unit derived from the force exerted by a kilogramforce acting over a distance of one meter.
Conversion factor: 1 kgf•m = 9.80665 J 
Poundforce foot (lbf•ft): The poundforce foot is a unit derived from the force exerted by a poundforce acting over a distance of one foot.
Conversion factor: 1 lbf•ft = 1.35582 J 
Poundal foot (pdl•ft): The poundal foot is a unit derived from the force exerted by a poundal acting over a distance of one foot.
Conversion factor: 1 pdl•ft = 0.0421401 J 
Erg (erg): The erg is a unit of energy commonly used in the field of atomic and molecular physics. It is equal to one dyne (a unit of force) acting over a distance of one centimeter.
Conversion factor: 1 erg = 0.0000001 J 
Electronvolt (eV): The electronvolt is a unit of energy often used in atomic and particle physics. It represents the amount of energy gained by an electron when accelerated through an electric potential difference of one volt.
Conversion factor: 1 eV = 1.60218 * 10^(−19) J
Difference between "IT" and "th" units
The terms "IT" and "th" refer to different reference points for defining energy units. Here's the difference between "IT" and "th" in the context of energy measurement:

"IT" (International Table)
The "IT" in energy units stands for "International Table". It is a reference point based on the International Steam Table calorie. The International Table calorie (cal IT) is defined as 1/860th of a watthour (approximately 4.1868 joules). Energy units like BTU IT (British Thermal Unit, International Table) and Calorie IT (International Table Calorie) are based on this reference point. 
"th" (Thermochemical)
The "th" in energy units stands for "thermochemical". It is a reference point based on the Thermochemical Calorie. The Thermochemical Calorie (cal th) is defined as exactly 4.184 joules. Energy units like BTU th (British Thermal Unit, Thermochemical) and Calorie th (Thermochemical Calorie) are based on this reference point.
The main difference between "IT" and "th" lies in the reference points used to define the units. While the numerical values of the units are slightly different, the underlying concept of measuring energy remains the same. It's important to note which specific reference point is being used when working with energy units to ensure accurate measurements and conversions.