How Much Should 3-Month-Old Weigh?

The average weight of a 3-month-old baby is 12.9 pounds for girls and 14.1 pounds for boys; average length is 23.5 inches for girls and 24.2 inches for boys. Whether baby's close to the average or not, the important thing is that they're growing at a healthy rate.

What is the ideal weight for a 3-month-old baby?

The normal weight for a 3-month-old baby girl is between 9.7-17.2 pounds, while the normal weight for a 3-month-old baby boy is between 10.6-18.3 pounds. For girls, the 50th percentile—right in the middle of the pack—would be about 12.8 pounds; for boys, the 50th percentile would be about 14.1 pounds.

How often should you weigh a 3-month-old?

After the first 2 weeks, your baby should be weighed: no more than once a month up to 6 months of age. no more than once every 2 months from 6 to 12 months of age. no more than once every 3 months over the age of 1.