Energy Converter
Convert between 8 energy units.
About Energy
Energy, work and heat all share the same units. The joule is the SI one; a calorie is 4.184 J, and the “calorie” on food labels is really a kilocalorie — a thousand of them. Electricity is billed in kilowatt-hours, and 1 kWh is 3.6 million joules. A 2,000 kcal daily diet works out at about 8.4 megajoules.
Conversion table — 1 unit in joule
| Unit | Joule |
|---|---|
| Joule | 1 |
| Kilojoule | 1000 |
| Calorie | 4.184 |
| Kilocalorie | 4184 |
| Watt-hour | 3600 |
| Kilowatt-hour | 3600000 |
| BTU | 1055.06 |
| Electronvolt | 1.6022e-19 |
Energy conversions — frequently asked
- What is 1 Joule in kilojoule?
- 1 Joule = 0.001 kilojoule.
- What is 1 Joule in calorie?
- 1 Joule = 0.239006 calorie.
- What is 1 Joule in kilocalorie?
- 1 Joule = 0.000239006 kilocalorie.
- What is 1 Joule in watt-hour?
- 1 Joule = 0.000277778 watt-hour.
- What is 1 Joule in kilowatt-hour?
- 1 Joule = 2.7778e-7 kilowatt-hour.
- What is 1 Joule in btu?
- 1 Joule = 0.000947817 btu.
Common conversions
Related converters
About Unit Converter
A unit converter changes a measurement from one unit to another. Pick a category — length, weight, temperature, data, area, speed, and 75+ more, including engineering and scientific units like pressure, torque, and viscosity — enter a value, and get an accurate conversion instantly. It runs in your browser with no sign-up and nothing to install.
Frequently asked questions
- How many unit categories are supported?
- Over 75, from everyday units (length, mass, temperature, volume, area, speed, data storage) to technical and scientific ones (energy, pressure, torque, viscosity, molar concentration, luminance, and more).
- Does it convert engineering and scientific units?
- Yes. Alongside common units it covers engineering and scientific categories — force, pressure, torque, thermal, flow, radiology, and CSS/typography units — with precise conversion factors.
- Are the conversions accurate?
- Yes. Conversions use standard factors and precise formulas, including non-linear ones like temperature, so results are exact.
- Do I need to install an app?
- No download needed — it's a free web app that runs in any modern browser on phone, tablet, or desktop, with nothing to install and nothing sent anywhere.
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