Calorie Converter
Convert food Calories (kcal), kilojoules, small calories and joules with the exact thermochemical energy conversion and clear food-label terminology.
Enter or adjust the values above, then calculate.
Convert food Calories, kilojoules and joules without unit confusion
Convert food Calories (kcal), kilojoules, small calories and joules with the exact thermochemical energy conversion and clear food-label terminology.
Inputs this tool uses
- Energy value
- Convert from
What you get
Exact energy-unit conversion using the thermochemical calorie definition.
How to use the Calorie Converter
- Enter energy value, convert from.
- Select any method, activity level or option shown on this page, then choose Calculate.
- Read the main result together with the supporting values, method, assumptions and limitations below before using the estimate.
How this calculation works
Example calculation
The sample values loaded into the calculator produce 2,092 kJ. This example exists to show how the output is structured; replace the sample values with your own inputs for your calculation.
Assumptions and limitations
- Food-label Calories are kilocalories (kcal), while the lowercase scientific calorie (cal) is 1/1,000 of a kcal.
- The conversion factor is exact, but a food label or another calculator can still contain rounded or estimated source values.
Sources and review status
Source set last verified 2026-09-25. No clinician review is claimed unless a real named reviewer is displayed.
Questions people ask about Calorie Converter
How many kilojoules are in one food Calorie?
One food Calorie is one kilocalorie (kcal), and 1 kcal equals exactly 4.184 kJ under the thermochemical definition.
Is a calorie the same as a kilocalorie?
In nutrition, the word Calorie usually means kilocalorie (kcal). In physics, a lowercase calorie (cal) is 1/1,000 of a kilocalorie, so the unit label matters.
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