kg is for kilogram-- kilo mean 1000-- 1000 grams in a kg, so multiply by 1000 convert g to kg.
Just move the decimal 3 places to the right to get 640 g = 0.64 kg.
1 kg = 1000 g
1000 g = 1 kg
one kg is 1000 g
1 kg = 1000 g
1 g = 0.001 kg
1kg = 1000g kg = kilogram g= gram
12500g
9.438kg
5500
5000
0.584kg
1KG = 1000 g