Calories to Megajoules Converter
Enter the energy in calories below to convert it to megajoules.
Convert Calories to Megajoules
Enter a value in calories (cal) to convert to megajoules (MJ).
Gram Calorie to Megajoule Conversion Table
Table showing various gram calorie measurements converted to megajoules. Click any preset value or arrow to load it into the converter.
| Calories (cal) | Megajoules (MJ) |
|---|---|
| 1 cal | 0.000004184 MJ |
| 10 cal | 0.00004184 MJ |
| 100 cal | 0.0004184 MJ |
| 1,000 cal | 0.004184 MJ |
| 10,000 cal | 0.04184 MJ |
| 100,000 cal | 0.4184 MJ |
| 1,000,000 cal | 4.184 MJ |
| 5,000,000 cal | 20.92 MJ |
| 10,000,000 cal | 41.84 MJ |
| 25,400,000 cal | 106.2736 MJ |
How to Convert Calories to Megajoules
To convert calories to megajoules, multiply the energy by the following conversion ratio: 0.000004184 megajoules/gram calorie.
Since one gram calorie is equal to 0.000004184 megajoules, you can use this simple formula to convert:
The energy in megajoules is equal to the energy in calories multiplied by 0.000004184.
For example, here's how to convert 5 calories to megajoules using the formula above.
How Many Megajoules Are in a Gram Calorie?
There are 0.000004184 megajoules in a gram calorie, which is why we use this value in the formula above.
Our gram calorie to megajoule calculator automatically converts your energy measurements with full decimal and scientific precision across US customary, imperial, and SI metric standards.
Calories and megajoules are both units used to measure energy. Keep reading to learn more about each unit.
What Is a Gram Calorie?
A gram calorie is a unit of energy equal to 4.184 joules (J), the base unit for energy. Thermochemical gram calorie defined as 4.184 Joules. [1]
The gram calorie is classified as a standard unit of energy. Calories can be abbreviated as cal; for example, 1 gram calorie can be written as 1 cal.
When working with calories (cal) in formulas or technical specifications, always verify whether your target system uses SI metric, US customary, or British imperial standards.
In practice, calories (cal) are widely used across standard energy applications within international standard workflows, engineering documentation, and technical data sheets.
What Is a Megajoule?
A megajoule is a unit of energy equal to 1,000,000 joules (J), the base unit for energy. Equal to 1,000,000 Joules. [2]
The megajoule is classified as an International System of Units (SI) unit of energy. Megajoules can be abbreviated as MJ; for example, 1 megajoule can be written as 1 MJ.
In the metric system, "mega" is the standard SI prefix for millions, or 10⁶. This makes the megajoule (MJ) a convenient decimal multiple of the joule (J).
In practice, megajoules (MJ) are widely used across large-scale industrial, bulk, and macro-level energy specifications within International System of Units (SI) workflows, engineering documentation, and technical data sheets.
When converting energy between calories (cal) and megajoules (MJ), keep full floating-point precision (1 cal = 0.000004184 MJ; 1 MJ = 239,005.7361377 cal) during intermediate calculations and round only the final megajoule figure to match your instrument tolerance.
More Gram Calorie & Megajoule Conversions
Need to calculate in the opposite direction? Use our megajoules to calories calculator to switch your starting unit immediately. You can also explore related tools such as converting megajoules to calories, converting calories to joules, or converting calories to kilocalories.
Convert from Calories
Frequently Asked Questions
References
- [1]NIST CODATA StandardNIST CODATA (CODATA Energy & Thermodynamic Constants)·Energy Metrology Standard — Calories (cal) to Megajoules (MJ)
- [2]NIST SP 811 SpecificationNIST SP 811 (NIST SP 811 App. B.9 (Energy, Work & Heat))·Unit Specifications: Gram Calorie (cal) (cal) & Megajoule (MJ)
- [3]BIPM ReferenceBIPM (Derived SI Unit: Joule (J))·Conversion Factors & Mathematical Basis (cal to MJ)