5kcal是多少kJ？
5kcal = 20.92kJ
是20.92kJ，所以说成21kJ也没问题——四舍五入的误差在0.5%以内。
反过来，5kJ是多少kcal？
5kJ = 1.2kcal
计算公式: kJ = kcal × 4.184
该数值前后的 kcal → kJ
0.5 kcal2.09kJ
1 kcal4.18kJ
1.5 kcal6.28kJ
2 kcal8.37kJ
2.5 kcal10.46kJ
3 kcal12.55kJ
3.5 kcal14.64kJ
4 kcal16.74kJ
4.5 kcal18.83kJ
5 kcal20.92kJ
5.5 kcal23.01kJ
6 kcal25.1kJ
6.5 kcal27.2kJ
7 kcal29.29kJ
7.5 kcal31.38kJ
8 kcal33.47kJ
8.5 kcal35.56kJ
9 kcal37.66kJ
9.5 kcal39.75kJ
10 kcal41.84kJ