Some of these changes can alter both their weight and their height. In the United States, 13-year-old children typically weigh anywhere from 60 pounds to 115 pounds, with an average weight of about 93 pounds.

The reality is several factors affect the average weight of a 13-year-old. Factors like genetics, health, and teen diet can play major roles. With this information in hand, your best bet is to get as accurate an idea of your son's health as possible by meeting with his pediatrician, so you know how to help him succeed beyond his teen years.

Average Weight For 13-Year-Olds - Girls And Boys

Average Weight For 13-Year-Olds - Girls And Boys

Most children who grow and develop normally fall within the Healthy Weight Zone.

A child's total body weight is made up of two parts:

Body Fat

The soft tissue is found under the skin that stores excess calories as energy. It also cushions and insulates vital organs and protects them from injury. The amount of body fat a child has is determined by how much of the body is fat, not by how much they weigh.

Muscle Mass And Bone Density

Muscle mass is the hard tissue that helps with movement, strength, growth, and burning calories. Bone density helps support the body's weight and protect internal organs such as the brain and heart.

The Centers for Disease Control and Prevention (CDC) have set guidelines for healthy Weight and body mass index (BMI) in children.

Healthy Weight For A 13-Year-Old:

A child's healthy Weight depends on their height, gender, and age. The CDC uses a measurement called BMI, or body mass index, a simple way to see if your child is at a healthy weight. Many calculators online can help you determine your child's BMI.

A 13-year-old boy who weighs more than 85 pounds has an unhealthy weight. A girl of the same age who weighs more than 95 pounds has an unhealthy weight.

The CDC's Healthy Weight Guidelines:

A 13-year-old boy who is 4' 10" should weigh between 92 and 103 pounds; a girl of the same age who is 4' 6" should weigh between 97 and 110 pounds.

The average weight for 13-year-olds is between 90-100 lbs.

For a male, the average height is 5'2", while the average female height is 4'8".


A child's BMI is calculated by dividing their weight in kilograms by their height in meters squared. To determine if a child is overweight, their BMI should be greater than or equal to the 85th percentile for children of the same age and sex.

BMI is just one way of looking at body size and shape — it doesn't account for muscle mass or bone structure. For example, high-performance athletes often have BMIs that would qualify them as overweight under certain criteria but still fall into the normal range because they have more muscle mass than others.

Person’s BMI Calculator

A person's BMI is calculated by dividing their weight in kilograms by their height in meters squared (kg/m2). For adults, the World Health Organization has established categories of BMI based on health risks associated with different ranges of BMI values:

BMI less than 18.5 = underweight; healthy weight range; recommended range for children and teens ages 2 to 19.

BMI between 18.5 and 24.9 = healthy weight range; recommended range for children ages 2 to 19.

BMI between 25 and 29.9 = overweight; at risk of overweight; recommended range for children ages 2 to 19.

Weight is one of the most important factors to consider when evaluating your child's health. The average weight for 13-year-olds is between 90-100 lbs. Girls tend to be taller than boys until they reach puberty.

The Centers for Disease Control and Prevention (CDC) recommends that you monitor your child's height and weight at every well-child checkup, but you should also know the following:

  • BMI 30 or higher= obese; at risk of overweight
  • BMI 25-29.9= overweight; at risk of overweight
  • BMI 18.5-24.9= healthy weight range
  • BMI less than 18.5= underweight

Percentiles By Weight For 13-Year-Old Girls

Here are the percentiles by weight for 13-year-old girls:

























Percentiles By Weight For 13-Year-Old Boys

Here are the percentiles by weight for 13-year-old boys:

























Teenage girls & Boys Height




























Why Is My Child's Weight Important?

Gaining too much weight or losing too much can lead to health problems in the future, such as:


A child who is overweight or obese is at risk for developing type 2 diabetes, high cholesterol, and high blood pressure later in life. But even kids considered normal weight may have a high BMI (body mass index), which means they're still at risk for developing these conditions.

Cholesterol Problems

Doctors use the cholesterol levels in your blood to determine if you're likely to develop heart disease later in life because of high cholesterol levels. Children with high cholesterol levels may need medication to lower it, but this can help prevent them from developing serious health issues later.

Factors That Affect Weight

Many factors affect a child's weight, including genetics, environment, physical activity, and eating habits. If your child's BMI falls in the 85th percentile or above for their age group, talk to your doctor about ways to encourage healthy habits, like eating well and exercising regularly, so your child will reach a healthy weight.

A child's weight is affected by many factors, including genetics, environment, physical activity level, and eating habits.


Children with parents with a history of obesity or diabetes are more likely to become obese. If both parents are overweight or obese, their child is more likely to become overweight.


We live in an environment that promotes unhealthy eating habits and few opportunities for physical activity. Many schools have cut funding for physical education classes, and many students spend most of their day sitting at a desk in class rather than running around outside. This makes it more difficult for parents to teach their children healthy eating habits and promote healthy behaviors that will help them maintain a healthy weight.

Physical Activity Level

Only 1 in 4 children meets the recommended 60 minutes per day of physical activity. Children who do not get enough exercise tend to gain more weight over time than those who participate in regular physical activity programs like sports teams or dance classes.

Rate Of Development And Puberty

A child who develops earlier may weigh more than one who develops later. Puberty can also affect weight, especially for girls. Girls often gain about 5 pounds during puberty but may gain up to 20 pounds or more if they have a lot of body fat in their thighs and hips.


Some children have more muscle than others, which makes them heavier. Children who play sports or participate in other physical activities also tend to weigh more because they build muscle mass through exercise.

Body Composition

The ratio of body fat to lean muscle affects how heavy a child appears and how healthy she feels inside her skin. If your child's weight seems too high compared with her height, talk with her pediatrician or another healthcare provider about what might be causing this discrepancy and how best to address it.


The older a child gets, the more likely she is to have an increase in body fat — regardless of gender or race. This is because girls have higher estrogen levels than boys, which can lead to increased fat deposits in the hips, thighs, buttocks, and breasts.

Exercise Levels

Physical activity plays a role in determining whether children are overweight or not. Sedentary lifestyles are associated with higher rates of obesity among children than those who are active regularly.

Nutrition And Lifestyle Habit

Your child's growth has been influenced by genetics and environment — including family habits like diet, sleep patterns, and physical activity. These factors can continue to affect her weight throughout adolescence and into adulthood.

Family history. If other family members are overweight or obese, it is more likely that your child will also gain weight. And if one or both parents are overweight or obese, there's an increased risk of childhood obesity — especially if your child eats a lot of fast food and doesn't exercise regularly.


The age at which they enter puberty also contributes to how much weight they gain during this period of rapid growth. Girls who begin puberty at age 8 or 9 usually have an easier time than girls who start puberty at age 11 or 12 (or later). If your child has started puberty early, you may be concerned about her weight.

The average weight for a 13-year-old girl is about 112 pounds (51 kg). Some girls are heavier than this, and some are lighter.

At this age, it's common for boys to be taller than girls by several inches. Boys also weigh more on average than girls do.

The average height for a 13-year-old boy is about 5 feet 3 inches (160 cm). That's about 2 inches (5 cm) taller than the average 12-year-old boy.

Boys typically grow faster during adolescence than girls, especially between ages 10 and 14. But because boys' bodies are larger and they're generally heavier than girls, their growth spurts tend to be shorter than those of girls.

Wind Up

If your daughter is underweight, the first thing to do is to ensure she's eating enough and not having sudden or dramatic weight loss. As long as she's doing that, it might be worth getting her checked out by a doctor to rule out any underlying health problems.

Remember that BMI isn't a diagnostic tool but a measure. If your daughter is underweight, it may be worth speaking to your GP about what they recommend you do next.

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