kJ and Cal
calculator.

kJ and Cal conversion formula

For food labels, "Calories" usually means kilocalories. So a label value of 201 kcal is normally logged as 201 Calories in a calorie tracker, and 1 kJ is about 0.239 Calories.

Popular kJ to kcal conversions

These are common kilojoule figures from package labels, menu boards, and imported food entries. For a value that is not listed, type it into the calculator above, or open the kJ and Cal chart for every value from 10 kJ to 20,000 kJ.

Scale the result to the amount you ate

If the number is per 100g, the converted result is also per 100g. If it is per serving, the converted result stays per serving. The unit conversion changes kJ into kcal. It does not know how much food you ate until you add the label amount and amount eaten.

Example: a label says 840 kJ per 100g. That is about 201 Calories per 100g. If you ate 150g, the portion is about 301 Calories. Enter 100 as the label amount and 150 as amount eaten.

For a per-serving label, use the same idea. If one serving is 840 kJ and you ate two servings, enter label amount 1 and amount eaten 2.

Keep the label basis attached

That detail matters for imported foods. A package might show energy per 100g, per serving, and per pack in the same panel. Convert the column you actually plan to log, then scale the portion only if your eaten amount differs from that column.

Read how to convert kilojoules to Calories for the kcal naming convention, mental-math shortcut, and label-rounding explanation. Use the nutrition per 100g calculator if you need to scale protein, carbs, and fat too. If you would rather scan a table than type a value, the kJ to Calories chart lists every value from 10 kJ to 20,000 kJ. If you would rather keep your whole day in kilojoules instead of converting each label, the daily kilojoule intake calculator estimates maintenance in kJ and compares it with the 8,700 kJ label reference.

What to type into Mori after converting

Use one clean calorie value and keep the serving note beside it. For example: "Greek yogurt, imported label says 840 kJ per 100g, ate 150g, about 301 Calories, 15g protein." That note keeps the calculation auditable later.

The product rule is simple: kJ should be a display conversion of one energy value, not a second source of truth. Pick the calorie value you want to track, keep the original label note if useful, and avoid saving separate numbers that describe the same serving.

What this calculator does not do

It does not verify whether the label is correct or calculate protein, carbs, and fat from the package. It converts the energy value and scales it to the portion you enter.

If a label already shows both kJ and kcal, prefer the printed calorie value unless you have a reason to check the math. Small differences can come from rounding.