Convert kilocalories to megajoules

1 kcal=0.004184MJ

Use the converter below to change any kilocalories value into megajoules instantly — with formula, conversion table, and real-world examples.

You have

Equals

0.004184

Conversion formula

Forward

megajoules = kilocalories × 0.004184

Reverse

kilocalories = megajoules × 239.006

Example: 10 kcal × 0.004184 = 0.04184 MJ.

About both units

From

Kilocalorie

kcal

The kilocalorie equals 1000 small calories or 4184 joules. This is the nutrition "Calorie" (capital C in some US labels). EU and UK labels always say kcal; US labels say Calories. Adult daily intake is about 2000 kcal.

Real-world: Adult daily intake: ~2000 kcal. Banana: 90 kcal. Big Mac: 550 kcal. 30 min running: ~300 kcal burned.

Read full kilocalorie reference →

Megajoule

The megajoule equals 1,000,000 joules. Used for fuel energy content, large-scale mechanical work and in some European natural-gas billing. A litre of petrol contains about 34 MJ of energy.

Real-world: 1 L petrol: ~34 MJ. 1 L diesel: ~38 MJ. Tesla Model 3 full charge: ~270 MJ.

Read full megajoule reference →

Kilocalorie to Megajoule conversion table

Common kilocalories to megajoules values for quick reference.

Kilocalorie (kcal)	Megajoule (MJ)
1 kcal	0.004184 MJ
10 kcal	0.04184 MJ
100 kcal	0.4184 MJ
500 kcal	2.092 MJ
1,000 kcal	4.184 MJ
5,000 kcal	20.92 MJ
10,000 kcal	41.84 MJ
50,000 kcal	209.2 MJ
100,000 kcal	418.4 MJ
500,000 kcal	2,092 MJ

Tips & common mistakes

Quick tips

1 kcal = 4.184 kJ.
US "Calorie" (with capital C) = 1 kcal.
Apps and smartwatches track active energy in kcal.

Avoid these

Reading food "Calories" as gram calories — factor of 1000 off.
Treating all calorie values as comparable — macros (fat, protein, carb) differ in energy density.
Counting kcal without portion size leads to underestimates.

Frequently asked questions

How many megajoules in a kilocalorie?

One kilocalorie equals 0.004184 megajoules.

How do I convert kilocalories to megajoules?

Multiply the kilocalorie value by 0.004184 to get the equivalent in megajoules.

What is 100 kilocalories in megajoules?

100 kilocalories equals 0.4184 megajoules.

Is a kilocalorie bigger than a megajoule?

No. 1 kilocalorie equals 0.004184 megajoules, so one kilocalorie is smaller.

How to convert kilocalories to megajoules without a calculator?

Multiply by 0 for a quick estimate; use a calculator for precise results.

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