Convert Kilocalories to Megajoules
1 kilocalorie (kcal) equals 0.004184 megajoules (MJ).
1 kcal = 0.004184 MJ
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk kilocalorie to megajoule converter to paste a column from Excel.
How to Convert Kilocalorie to Megajoule
- 1 kcal = 0.004184 MJ
- 1 MJ = 239.0057361 kcal
- Example: convert 15 kcal to MJ: 15 kcal = 15 × 0.004184 MJ = 0.06276 MJ
Reference conditions. kcal: Thermochemical kilocalorie (food Calorie), 4184 J exactly.
Formula
MJ = kcal × 0.004184
or MJ = kcal ÷ 239.0057361377
Derivation from SI units:
- 1 kcal = 1000 cal = 4184 J (exact)
- 1 MJ = 10⁶ J
- 1 kcal = 4184 J ÷ 1000000 J per MJ = 0.004184 MJ
Both units are defined exactly, so the factor is exact. Kilocalorie definition: kilocalorie; Megajoule definition: megajoule.
Worked examples
- A reading of 200 kcal converts to 0.8368 MJ.
200 kcal × 0.004184 = 0.8368 MJ - A value of 1500 kcal is 6.276 MJ.
1500 kcal × 0.004184 = 6.276 MJ
Kilocalorie to Megajoule conversion table
| Kilocalories (kcal) | Megajoules (MJ) |
|---|---|
| 1 kcal | 0.004184 MJ |
| 50 kcal | 0.2092 MJ |
| 100 kcal | 0.4184 MJ |
| 150 kcal | 0.6276 MJ |
| 200 kcal | 0.8368 MJ |
| 250 kcal | 1.046 MJ |
| 300 kcal | 1.2552 MJ |
| 500 kcal | 2.092 MJ |
| 1000 kcal | 4.184 MJ |
| 1500 kcal | 6.276 MJ |
| 2000 kcal | 8.368 MJ |
| 2500 kcal | 10.46 MJ |
| 3000 kcal | 12.552 MJ |
| 3500 kcal | 14.644 MJ |
Where it's used
Kilocalories are used for food and diet energy (2000 kcal reference intake), while megajoules appear in fuel heating values (natural gas ≈ 38 MJ/m³, diesel ≈ 45 MJ/kg). Both measure energy, work and heat, so the conversion is a fixed factor.
Kilocalorie to other energy units
| Conversion | 1 kcal equals |
|---|---|
| kilocalorie to joule | 4184 J |
| kilocalorie to kilojoule | 4.184 kJ |
| kilocalorie to megajoule | 0.004184 MJ |
| kilocalorie to calorie | 1000 cal |
| kilocalorie to watt-hour | 1.162222222 Wh |
| kilocalorie to kilowatt-hour | 0.001162222222 kWh |
| kilocalorie to BTU | 3.965666831 BTU |
| kilocalorie to therm | 0.00003966613703 thm |
| kilocalorie to electronvolt | 2.611447397 × 10²² eV |
| kilocalorie to foot-pound | 3085.960033 ft·lbf |
| kilocalorie to erg | 41840000000 erg |
Frequently asked questions
How many megajoules are in 1 kilocalorie?
1 kcal = 0.004184 MJ.
How do I convert kilocalories to megajoules?
Multiply the value in kcal by 0.004184, or divide it by 239.0057361. For example, 15 kcal × 0.004184 = 0.06276 MJ.
Is the kcal to MJ conversion exact?
Yes. Both units are defined exactly, and 1 kcal is exactly 0.004184 MJ.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "kilocalorie (thermochemical)".
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Kilocalories to Megajoules. Retrieved October 17, 2026, from https://scientificconverters.com/energy/kilocalories-to-megajoules/
IEEE
Scientific Converters, "Convert Kilocalories to Megajoules," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/energy/kilocalories-to-megajoules/