Convert Calories to Kilocalories
1 calorie (cal) equals 0.001 kilocalories (kcal).
1 cal = 0.001 kcal
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk calorie to kilocalorie converter to paste a column from Excel.
How to Convert Calorie to Kilocalorie
- 1 cal = 0.001 kcal
- 1 kcal = 1000 cal
- Example: convert 15 cal to kcal: 15 cal = 15 × 0.001 kcal = 0.015 kcal
Reference conditions. cal: Thermochemical calorie, 4.184 J exactly. The International Table calorie is 4.1868 J. kcal: Thermochemical kilocalorie (food Calorie), 4184 J exactly.
Formula
kcal = cal ÷ 1000
Derivation from SI units:
- 1 cal (thermochemical) = 4.184 J (exact)
- 1 kcal = 1000 cal = 4184 J (exact)
- 1 cal = 4.184 J ÷ 4184 J per kcal = 0.001 kcal
Both units are defined exactly, so the factor is exact. Calorie definition: calorie; Kilocalorie definition: kilocalorie.
Worked examples
- A reading of 100 cal converts to 0.1 kcal.
100 cal × 0.001 = 0.1 kcal - A value of 1000 cal is 1 kcal.
1000 cal × 0.001 = 1 kcal
Calorie to Kilocalorie conversion table
| Calories (cal) | Kilocalories (kcal) |
|---|---|
| 1 cal | 0.001 kcal |
| 10 cal | 0.01 kcal |
| 100 cal | 0.1 kcal |
| 250 cal | 0.25 kcal |
| 500 cal | 0.5 kcal |
| 1000 cal | 1 kcal |
| 4184 cal | 4.184 kcal |
| 10000 cal | 10 kcal |
Where it's used
Calories are used for chemistry and calorimetry, while kilocalories appear in food and diet energy (2000 kcal reference intake). Both measure energy, work and heat, so the conversion is a fixed factor.
Calorie to other energy units
| Conversion | 1 cal equals |
|---|---|
| calorie to joule | 4.184 J |
| calorie to kilojoule | 0.004184 kJ |
| calorie to megajoule | 0.000004184 MJ |
| calorie to kilocalorie | 0.001 kcal |
| calorie to watt-hour | 0.001162222222 Wh |
| calorie to kilowatt-hour | 0.000001162222222 kWh |
| calorie to BTU | 0.003965666831 BTU |
| calorie to therm | 3.966613703 × 10⁻⁸ thm |
| calorie to electronvolt | 2.611447397 × 10¹⁹ eV |
| calorie to foot-pound | 3.085960033 ft·lbf |
| calorie to erg | 41840000 erg |
Frequently asked questions
How many kilocalories are in 1 calorie?
1 cal = 0.001 kcal.
How do I convert calories to kilocalories?
Multiply the value in cal by 0.001, or divide it by 1000. For example, 15 cal × 0.001 = 0.015 kcal.
Is the cal to kcal conversion exact?
Yes. Both units are defined exactly, and 1 cal is exactly 0.001 kcal.
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, "calorie (thermochemical) (cal_th)".
- 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)".
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 Calories to Kilocalories. Retrieved October 17, 2026, from https://scientificconverters.com/energy/calories-to-kilocalories/
IEEE
Scientific Converters, "Convert Calories to Kilocalories," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/energy/calories-to-kilocalories/