The recommended height and weight for an 8-year-old isn’t as clear-cut as the recommended inches and pounds from a specific chart. There may be an average height and weight for a child of any age, but these values for height and weight are not necessarily a good indication of whether your child is growing healthily.
Children of a given age fall within a height range, so the recommended height of an 8-year-old is typically based on percentiles. The 50th percentile is the median height for children, which means that roughly 50 percent of children of the same age and gender will be above this height and the other 50 percent will be below it. For both girls and boys at 8 years old, the median height is about 50 inches, or right around 4 feet tall, according to the Centers for Disease Control and Prevention.
The number of pounds your child weighs isn’t used alone to determine weight status. Instead, you should calculate body mass index to clarify if your child is a healthy weight. To arrive at this number, divide weight in pounds by height in inches and then divide this number by height in inches again. From there, multiply this number by 703 to arrive at your child’s BMI. An 8-year-old boy weighing 50 lbs. at a height of 4 feet 1 inch tall has a BMI of 14.6. This number is then placed on a growth chart to arrive at a percentile. It’s this percentile that indicates if your child is at a healthy weight.
A BMI that places an 8-year-old above the 4th percentile, yet below the 85th percentile generally means your child is a healthy weight. BMIs below the 5th percentile indicate underweight, while above the 84th means overweight and above the 95th means obese. As mentioned before, an 8-year-old boy weighing 50 lbs. at a height of 4 feet 1 inch tall has a BMI of 14.6. This places him at the 20th percentile, which means he’s a healthy weight for his age and height.
Just because your 8-year-old falls within a certain percentile doesn’t necessarily mean he’s underweight, overweight or obese for his age and height. When it comes to children, BMI is only used as a screening tool for potential weight problems. Your pediatrician will likely test skinfold thickness and assess diet and level of physical activity to determine if excess fat is an issue.