12 units · base: J
Convert energy: J, kJ, cal, kcal, Wh, kWh, BTU, eV…
Equivalences of 1 joule (J) in all available energy units.
The most searched energy conversions in everyday use.
Type the value to convert in the "Value" field of the energy converter.
Select the source unit ("From") and the target unit ("To") from the 12 available units.
The result appears instantly, calculated according to International System of Units (SI) standards.
Convert energy values for classes, lab work, or scientific reports with SI-compliant precision.
Handle energy units from different systems (metric, imperial) in your professional projects.
Quickly understand energy values shown on foreign products, recipes, or instruction manuals.
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Convert energy: J, kJ, cal, kcal, Wh, kWh, BTU, eV… This category includes 12 units, with Joule (J) as the reference unit. Calculations are performed directly in your browser, in full privacy and without any installation.
All conversions are based on the official factors of the International System of Units (SI) and ISO standards. No intermediate rounding is applied to preserve precision. Calculations are performed directly in your browser, in full privacy and without any installation.
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This converter supports 12 units: Joule (J), Kilojoule (kJ), Mégajoule (MJ), Calorie (cal), Kilocalorie (kcal), Wattheure (Wh), Kilowattheure (kWh), BTU (BTU)…. All are accessible via the converter selector.
Convertly UNITS covers 14 unit categories: length, mass, temperature, speed, volume, area, and more. Also try length / mass.
14 unit categories based on the International System of Units (SI): length, mass, temperature, energy, and more.
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