My baby is 4 months old.. before i ws using born baby huggies, now which size should i buy

A. Size 2. Next up are size 2 diapers. Designed for babies who are between 12 to 18 pounds, expect your baby to wear this size usually between the ages of 3 and 8 months. That means that for most of their first year, they'll be in size 2 diapers, using them up at a rate of around 8 or 9 diapers per day.