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Energy Converter - Convert Joules Calories kWh BTU Online Free | The MuffinPost
Free Unit Converter

Energy Converter

Convert energy units instantly. Switch between joules, kilojoules, calories, kilocalories, watt-hours, kilowatt-hours, BTU, electronvolts and more.

Convert Energy

Type any energy value to convert it instantly.
Choose the original energy unit.
Choose the unit you want to convert to.
Quick References 1 kJ = 1,000 J
1 cal = 4.184 J
1 kcal = 4,184 J
1 kWh = 3,600,000 J

Result

3,600,000 J 1 kilowatt-hour equals 3,600,000 joules
3,600,000Joules
3,600Kilojoules
860,421Calories
860.421Kilocalories
1,000Watt-hours
3,412.14BTU

How to Use the Energy Converter

Convert energy units in three simple steps.

1. Enter energy

Type the energy value you want to convert.

2. Choose units

Select the original energy unit and the target unit.

3. View result

See the converted value and common energy equivalents instantly.

Fast energy conversion for science, nutrition and electricity.

This Energy Converter helps students, engineers, electricians, fitness users and everyday users convert energy values across physics, food, heating and electricity units with browser-based calculations.

✅ Convert joules, calories and kilocalories
✅ Supports watt-hours, kWh and BTU
✅ Instant results while typing
✅ Works directly in your browser

Energy Converter FAQ

Common questions about converting energy units.

How many joules are in one kilowatt-hour?

One kilowatt-hour equals exactly 3,600,000 joules.

How many joules are in one calorie?

One small calorie equals 4.184 joules. One food Calorie equals 4,184 joules.

What is BTU?

BTU means British thermal unit. It is commonly used for heating, cooling and energy measurement.

Does this converter use a backend?

No. All energy conversions run directly in your browser with HTML, CSS and JavaScript.