Is 130lbs under weight for a 15 year old?

The answer is: it depends

A 15-year-old boy who is 5 feet tall and weighs 130 pounds has a body mass index (BMI) of 19.6, which is considered to be in the healthy weight range. However, a 15-year-old girl who is 5 feet tall and weighs 130 pounds has a BMI of 22.5, which is considered to be overweight.

BMI is a measure of body fat based on height and weight. It is used to screen for weight problems in adults, but it is not always a reliable indicator of health in children and adolescents. Some children and adolescents may have a high BMI but still be healthy, while others may have a low BMI but still be at risk for health problems.

It is important to talk to your doctor about your child's weight and growth if you have any concerns. Your doctor can assess your child's overall health and development and make recommendations if needed.