Energy Converter: Cal & Joule

Energy Converter is a clean, fast tool for converting between every energy unit you actually use — calorie (cal), kilocalorie (kcal), joule (J), kilojoule (kJ), watt-hour (Wh), kilowatt-hour (kWh), and BTU.

Whether you are tracking calories burned at the gym, estimating power draw from a home appliance or electric vehicle, or wrestling with a physics problem set, the conversion happens the moment you type.

WHO IS THIS FOR
- Fitness and diet trackers — translate food calories into kcal or kJ
- Students and teachers — physics, chemistry, thermodynamics homework
- Engineers and researchers — quick sanity checks on energy budgets
- Anyone curious about how much energy a kWh actually represents

KEY FEATURES
- 7 energy units in one screen: cal, kcal, J, kJ, Wh, kWh, BTU
- Real-time conversion — no submit button, no waiting
- Color-coded units for instant visual distinction
- Adjustable font size for accessibility
- Works fully offline — no signup, no account, no internet required
- Lightweight: fast cold start
- Clean, distraction-free interface

WHY THIS APP
Most converter apps cram dozens of unit categories into one cluttered screen. Energy Converter does one thing and does it well. Open the app, pick a unit, type a number — you have your answer.

No subscription. No login.

REQUEST A UNIT
Need a unit we don't support yet? Send a request through the feedback option. We add new units in regular updates.

PRIVACY
This app does not collect personal information. Calculations happen entirely on your device.

Download Energy Converter and stop guessing what a kilojoule means.

Recent changes:
Traditional Chinese devices (Taiwan, Hong Kong) now open in Traditional Chinese. Minor stability improvements.