Energy Converter
Convert energy between joules, kilojoules, calories, kilocalories, watt-hours, kWh, and BTU.
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- Accurate results
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- Works on all devices
Enter an energy value and choose a from/to unit to convert between joules, calories, kWh, and BTU.
Your result
4,184
Converted value
AI explanation
Formula
Converted value = amount × (from-unit-to-joules factor) ÷ (to-unit-to-joules factor)Worked example
1 kilocalorie to joules
| Field | Value |
|---|---|
| Amount | 1 |
| From unit | kcal |
| To unit | j |
| Converted value | 4184 |
Assumptions
- Uses the thermochemical calorie (1 cal = 4.184 J exactly), the definition used in nutrition and chemistry.
- "Calories" on Indian and global food labels are actually kilocalories (1 food Calorie = 1 kcal) — use the Calorie Calculator for diet-specific context.
Frequently asked questions
Is a food "Calorie" the same as a calorie?
No — a food label's "Calorie" (capital C) is actually 1 kilocalorie (1,000 small calories). This converter's "kcal" unit matches food-label Calories.
How many joules are in 1 kWh?
1 kWh = 3,600,000 J exactly — this is how electricity bills convert to the SI energy unit.
What is BTU used for?
BTU (British Thermal Unit) is commonly used for air conditioner and heater capacity ratings, especially in US-market appliance specifications.