Energy Conversion Calculator
Convert between different energy units including joules, calories, kWh, BTU, and more
Energy Unit Converter
Joules
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Conversion Result
All Unit Conversions
| Unit | Symbol | Value |
|---|---|---|
| Joules | J | 1 |
| Kilojoules | kJ | 0.001 |
| Calories | cal | 0.2390057361 |
| Kilocalories | kcal | 0.0002390057 |
| Watt Hours | Wh | 0.0002777778 |
| Kilowatt Hours | kWh | 2.777778e-7 |
| British Thermal Units | BTU | 0.0009478134 |
| Electronvolts | eV | 6.241509e+18 |
| Foot-pounds | ft·lbf | 0.7375621212 |
| Ergs | erg | 10,000,000 |
| Therms | thm | 9.478170e-9 |
| Tons of TNT | t TNT | 2.390057e-10 |
| Quads | quad | 9.478170e-19 |
| Hartrees | Eh | 2.293712e+17 |
Common Energy Conversions
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Quick Reference
Understanding Energy Units
What is Energy?
Energy is the capacity to do work or produce change. It exists in many forms including kinetic energy (motion), potential energy (position), thermal energy (heat), electrical energy, chemical energy, and nuclear energy.
SI Base Unit - Joule
The joule (J) is the SI base unit of energy, named after James Prescott Joule. One joule equals the energy expended when applying a force of one newton through a distance of one meter.
Common Applications
- •kWh: Electricity billing and consumption
- •kcal: Food energy and nutrition
- •BTU: Heating and cooling systems
- •eV: Atomic and particle physics
Energy Conversion Examples
Household Energy
A typical household uses about 30 kWh per day, which equals 108 million joules or about 25,800 kcal of energy.
Food Energy
A slice of bread contains about 80 kcal, which equals 334,720 joules of chemical energy.
Atomic Scale
The ionization energy of hydrogen is 13.6 eV, which equals 2.18 × 10⁻¹⁸ joules.
Energy Conservation
Energy cannot be created or destroyed, only transformed from one form to another. This fundamental principle governs all energy conversions in the universe.