The difference between Adidas baby size 98 and 100 lies in height and age range.

1, height: size 98 is suitable for infants with a height of 90-98 cm, and size 100 is suitable for infants with a height of 98- 104 cm.

2. Age range: size 98 is suitable for 2-3 years old, and 100 is suitable for 3-4 years old.