Energy Converter Units
Convert joules, calories, kilowatt-hours and BTU.
Energy Converter is a free online tool that convert joules, calories, kilowatt-hours and BTU. It runs entirely in your web browser using plain JavaScript, so files are processed on your own device and never uploaded to a server. There is no sign-up, no file size limit imposed by the site, no watermark and no paid tier.
- Price
- Free — no account, no quota, no watermark
- Category
- Units
- Where it runs
- In your browser, on your device
- Files uploaded
- None
- Technology
- plain JavaScript
- Settings
- 3
- Works offline
- Yes, after the first visit
About Energy Converter
Energy Converter is one of 19 units tools on DuckyTools, and like all of them it runs entirely inside this page. Convert joules, calories, kilowatt-hours and BTU.
How to use it
- Enter value, from and to.
- Results update the moment anything changes.
The 3 settings
| Setting | What it does | Default |
|---|---|---|
| Value | A numeric value. | 1 |
| From | Choose from 10: Joules, Kilojoules, Megajoules, Calories (small), Kilocalories (food), Watt-hours…. | Kilowatt-hours |
| To | Choose from 10: Joules, Kilojoules, Megajoules, Calories (small), Kilocalories (food), Watt-hours…. | Megajoules |
Conversion reference
Exact factors used by this converter, expressed against joules (J). These are the defined values, not rounded approximations.
| Unit | Symbol | In J |
|---|---|---|
| Joules | J | 1 |
| Kilojoules | kJ | 1,000 |
| Megajoules | MJ | 1,000,000 |
| Calories (small) | cal | 4.184 |
| Kilocalories (food) | kcal | 4,184 |
| Watt-hours | Wh | 3,600 |
| Kilowatt-hours | kWh | 3,600,000 |
| BTU | BTU | 1,055.05585262 |
| Foot-pounds | ft·lb | 1.35581794833 |
| Electronvolts | eV | 1.602177 × 10^-19 |
Under the hood
| Runs on | plain JavaScript — runs the whole thing |
| Controls | Value, From, To |
Questions
What does the from option change?
It offers 10 choices — Joules, Kilojoules, Megajoules and Calories (small) and more. The default is Kilowatt-hours, which suits most cases; change it when your input or your destination calls for something specific.