Free online converter category

Energy Conversion Tools for Joules, BTU, Calories and kWh

Convert energy units such as joules, kilojoules, BTU, calories, kilocalories, kilowatt-hours, and electronvolts.

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Quick Converter

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Popular Energy Conversion Tools

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J

Joules to kJ conversion

Convert joules to kilojoules.

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J

Joules to BTU conversion

Convert joules to BTU.

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J

Joules to Calories conversion

Convert joules to calories.

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kJ

kJ to Joules conversion

Convert kilojoules to joules.

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BTU

BTU to kWh conversion

Convert BTU to kilowatt-hours.

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kWh

kWh to BTU conversion

Convert kilowatt-hours to BTU.

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cal

Calories to Joules conversion

Convert calories to joules.

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Common Formulas and References

Use these references as a quick guide. The converter or linked tools calculate the result automatically.

Referencekilojoules = joules ÷ 1000
Referencejoules = kWh × 3,600,000
Referencejoules = calories × 4.184

Energy Conversion Tools FAQ

Common questions about this category.

How many joules are in 1 kJ?

1 kJ equals 1000 joules.

How many joules are in 1 calorie?

1 calorie equals 4.184 joules.

What is kWh?

kWh means kilowatt-hour, a unit for electrical energy consumption.