Instantly convert energy values between British Thermal Units (BTU), joules, kilowatt-hours, therms, and both nutritional and thermochemical calories. Select a source unit, enter a value, and see the equivalent in your target unit.
1 BTU = 1055.05585262 J
1 Joule = 0.00094781712 BTU
Introduction
Energy conversion is the transformation of energy from one form into another to make it useful for human activity. While energy comes in many forms—including kinetic, potential, gravitational, and electrical—it follows the Law of Conservation of Energy: energy can be transferred or transformed, but the total amount always remains the same.
Different industries use different units to measure energy. Below are the most common standards:
| Symbol | Unit Name | Description |
|---|---|---|
| J | Joule | The standard SI unit of energy. |
| cal | Calorie | Often used in chemistry and nutrition. |
| Wh | Watt-hour | Commonly used for electricity consumption. |
| eV | Electron volt | Used in atomic and particle physics. |
| BTU | British Thermal Unit | Standard for heating and cooling systems. |
| kgce | kg Coal Equivalent | Energy released by burning 1 kg of coal. |
| kgoe | kg Oil Equivalent | Energy released by burning 1 kg of crude oil. |
| m³ Gas | Cubic Meter Gas | Energy equivalent of natural gas volume. |
| kpm | Kilopondmeter | Obsolete gravitational metric unit. |
| erg | Erg | CGS unit equal to joules. |
Energy conversion is the process of changing energy from one form into another. For example, gasoline's chemical energy, combined with electrical energy from a battery, produces mechanical (kinetic) energy to move a car. Similarly, electricity supplied to a television is converted into light and sound.
To convert between energy units, use the joule as the base. Multiply the value by the conversion factor for the source unit to obtain joules, then divide by the conversion factor for the target unit. For example, to convert from unit A to unit B, first convert A to joules using A's factor, then divide by B's factor to get the result in B.
Divide the heat energy (in joules) by the mass of the substance (in grams), then divide that result by the substance's specific heat capacity. For instance, 4,000 joules provided to 500 grams of water gives 4,000 ÷ 500 = 8; dividing 8 by the specific heat capacity yields the temperature change.
One MMBtu equals approximately 28.263682 cubic meters of natural gas at a defined temperature and pressure.
One atomic unit of energy (au) is equal to 4.359744 × 10⁻¹⁸ joules. To convert a value in au to joules, multiply it by 4.359744 × 10⁻¹⁸.
No, a kilojoule (kJ) is larger than a joule (J). One kilojoule equals 1,000 joules, and one megajoule (MJ) equals 1,000,000 joules. A watt, by contrast, is a unit of power, measuring energy per unit time.
A mole contains approximately 6.022 × 10²³ particles. To find the energy per particle in joules, divide one joule by Avogadro's number: 1 J/mol ÷ 6.022 × 10²³ mol⁻¹ ≈ 1.66054 × 10⁻²⁴ J per particle.
A kilojoule (kJ) is a unit of energy, just as a kilometre measures distance. In food energy, Calories (Cal) are also used. One kilojoule is approximately 0.2 Calories.
One joule (J) equals 0.001 kilojoules (kJ). To convert joules to kilojoules, multiply by 0.001 or divide by 1000. For instance, 100 J divided by 1000 equals 0.1 kJ.
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The standard unit of energy is the joule (J), defined as the work done by a force of one newton acting over one meter. Another common unit is the kilowatt-hour (kWh), which is the energy used by a one-kilowatt device running for one hour. Energy equals power multiplied by time (E = P × t).
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