Calories to Megajoules
Convert calories to megajoules instantly. 1 cal = 4.184e-06 MJ. Includes the exact factor, a conversion table of common values and the definition of both units.
How to convert calories to megajoules
To convert calories to megajoules, divide by 239005.7361376673 (multiply by 4.184e-06). The relationship is fixed, so the same factor works for any quantity — there is nothing to look up and nothing that changes with temperature, location or context.
MJ = cal × 4.184e-06
Calories to Megajoules conversion table
The values people look up most often, rounded for reading. Use the calculator above for anything in between.
| Calories | Megajoules |
|---|---|
| 1 cal | 4.184e-06 MJ |
| 2 cal | 8.368e-06 MJ |
| 3 cal | 1.255e-05 MJ |
| 5 cal | 2.092e-05 MJ |
| 10 cal | 4.184e-05 MJ |
| 20 cal | 8.368e-05 MJ |
| 25 cal | 0.0001046 MJ |
| 50 cal | 0.0002092 MJ |
| 100 cal | 0.0004184 MJ |
| 500 cal | 0.002092 MJ |
| 1,000 cal | 0.004184 MJ |
What is a calory?
The small calorie: energy to raise one gram of water by one degree.
What is a megajoule?
A million joules, used for fuel energy content and gas billing.
The formula
MJ = cal × 4.184e-06
Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.
How to use the Calories to Megajoules
- Type the number of calories you want to convert.
- Read the result in megajoules straight away — there is no button to press.
- Check the table below for the values that come up most often, or reverse the conversion with the linked megajoules to calories page.
Calories to Megajoules — frequently asked questions
How many megajoules are in a calory?
One calory equals 4.184e-06 MJ. MJ = cal × 4.184e-06
What is the formula to convert calories to megajoules?
The formula is MJ = cal × 4.184e-06. It is an exact definition rather than an approximation, so the conversion never drifts no matter how large the number.
How do I convert megajoules back to calories?
Divide instead of multiplying: one megajoule is 239005.7361376673 cal. The reverse converter is linked in the related tools list.
Is this conversion exact?
Yes. Both units are defined against the same base unit by international agreement, so the factor is exact — any rounding you see is only in the display, which you can widen by entering more decimal places.
Is this calories to megajoules free to use?
Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.
What people search for
This page answers each of these searches. They are the exact phrases visitors use to find the calories to megajoules.
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About this calculator
Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.
Last reviewed August 19, 2026 · Calculation runs client-side · No data collected · Report an error