Energy Converter
Convert energy values between joules, calories, watt-hours, and BTUs.. Use this smart bidirectional calculator to convert between different energy measurements instantly. See live results, calculation history, and exact formulas.
Energy Converter
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Formula
kJ = J × 0.001
To convert Joule to Kilojoule, use the formula displayed above.
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Recent History
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How to Convert Energy Units
To perform a conversion, look up the target unit's conversion factor relative to the base unit (joule). Below are the exact mathematical formulas for the most common energy unit pairs:
Energy Unit Conversion Charts
Here are the standard reference conversion charts displaying values from 1 to 20 for the most popular unit conversions:
Energy Converter FAQs
What is a Energy converter?
A Energy converter is a free online utility that transforms a measurement expressed in one unit of energy into its equivalent in another, such as converting Joule to Kilojoule.
How do you convert energy units?
To convert energy units, choose your from-unit and to-unit from the dropdown list in the tool above, then enter the value you wish to convert. The tool computes the result live in real time using exact SI conversion factor formulas.
What are the most popular energy conversions?
The most frequently performed energy conversions on our site are joules to calories, kwh to joules, kcal to joules. Our tool pre-calculates full charts and formulas for all of them.
Which energy units are supported?
We support all standard global SI (metric) and imperial units including Joule (J), Kilojoule (kJ), Calorie (cal), Kilocalorie (kcal), Watt-hour (Wh), Kilowatt-hour (kWh), and others.