what age does a baby double its weight
3.25 â 4.5 ounces per week. 4 â 5 ounces per week. 6-12 months. 1.75 â 2.75 ounces per week â¡. 2 â 4 ounces per week. [ click here to see tables in Metric Units ]â  It is acceptable for some babies to gain 4-5 ounces per week.â¡ The average breastfed baby doubles birth weight by 3-4 months. By one year, the typical breastfed baby will weigh about 2 1/2 â 3 times birth weight. 1Sources: