Energy Converter
Convert energy across 14 supported units with free instant calculations, formula guidance and examples. No sign-up required.
Calculations run in your browser. Results use approximately 12 significant digits, with floating-point rounding. Verify safety-critical measurements against applicable standards.
About Energy conversion
Convert between 14 energy units, including Joule (J), Kilojoule (kJ), MJ, GJ, Wh. Results update immediately when you edit the number or select another unit.
Use the exact unit labels: US and imperial variants are not always interchangeable.
Example calculation
1 J = 0.001 kJ. For linear quantities, multiply the source amount by the ratio of the two fixed reference-unit factors.
How to use
- Enter your amount in the field above.
- Select the original and destination energy units.
- Copy the calculated result or swap the units to reverse the conversion.
Frequently asked questions
Can I convert energy units for free?
Yes, the calculation runs locally in your browser with no sign-up.
Which units are supported?
This category currently includes 14 entries. Select the units from the dropdowns above.
Are the results suitable for professional use?
Use the exact unit labels: US and imperial variants are not always interchangeable. Check critical work against an applicable standard.
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Unit definition reference: NIST Guide to the SI.