Choosing the right energy conversion
Energy appears in several contexts: joules in SI calculations, kilowatt-hours on electricity bills, and BTU in heating and cooling. A small thermochemical calorie is not the same displayed unit as a food Calorie.
Always check the calorie convention. One food Calorie, written with an uppercase C in nutrition contexts, equals one kilocalorie or 1,000 small calories.
Common uses
- Electricity use and appliance energy
- Heating and cooling specifications
- Scientific and nutrition-unit comparisons
Quick energy utilities
These focused calculators provide a direct answer and the essential formula without requiring the longer background included in the in-depth guides.
Use converted values confidently
- One kilowatt-hour equals exactly 3.6 million joules.
- Treat food Calories as kilocalories, not small calories.
- BTU definitions can vary slightly; use the stated convention for technical work.