Convert Calories to Exajoules
Convert Calories (cal) to Exajoules (EJ) instantly and accurately.
Conversion Formula
EJ = cal × 4.184000000e-18
About Calories
A calorie (cal) - the thermochemical calorie - is exactly 4.184 J, defined as the heat to raise 1 g of water by 1°C. Standard since 1954. The calorie is the fundamental unit of heat measurement in thermochemistry: glucose combustion releases 669.9 kcal/mol; water vaporisation requires 539.7 cal/g. Bond dissociation energies in quantum chemistry are often quoted in kcal/mol. Note: the dietary Calorie (capital C) on food labels is 1 kcal = 4,184 J - a factor-of-1,000 difference that causes persistent confusion. 1 cal = 4.184 J = 1.163 × 10⁻³ Wh.
About Exajoules
An exajoule (EJ) is 10¹⁸ J - the scale of global energy consumption. World primary energy supply in 2022 was ~580-610 EJ: coal ~160 EJ; oil ~190 EJ; gas ~145 EJ; nuclear ~26 EJ; wind ~8 EJ; solar PV ~8 EJ. Global electricity generation of ~29,000 TWh = 104 EJ. Solar energy incident on Earth's atmosphere is ~5.5 × 10⁶ EJ/year - approximately 9,000× total human demand. Annual fossil fuel combustion releases ~490 EJ/year, producing ~36.8 Gt CO₂. 1 EJ = 10¹⁸ J = 277.78 TWh = 238.85 Mtoe.
Quick Reference Table
| Calories (cal) | Exajoules (EJ) |
|---|---|
| 1 cal | 4.184 × 10-18 EJ |
| 2 cal | 8.368 × 10-18 EJ |
| 5 cal | 2.092 × 10-17 EJ |
| 10 cal | 4.184 × 10-17 EJ |
| 25 cal | 1.046 × 10-16 EJ |
| 50 cal | 2.092 × 10-16 EJ |
| 100 cal | 4.184 × 10-16 EJ |