Question: how much should you weight at age 13?
Answer: Average weight of a 13-year-old girl The weight range for 13-year-old girls is between 76 and 148 pounds. Weights in the 50th percentile for this age land at 101 pounds. A weight in the 50th percentile means that of 100 13-year-old girls, 50 will weigh more while 50 will weigh less, and so on.