Growth Chart: What Do Your Kid’s Percentiles Really Mean?

Your pediatrician uses a growth chart to measure your child’s development. But, understanding what the numbers mean exactly can be confusing. We solve the mystery by telling you everything you need to know about the weight and height chart.


What is a growth chart?

A growth chart is just a record of how your child’s height, head circumference, and weight compare to other children of the same sex and age. Overall, the doctor is looking for a consistent growth pattern over time.

How do you read a height and weight chart?

To read the World Health Organization’s height and weight chart for babies ages newborn to 2-years-old, plot where the line for your child’s weight intersects with the line for their height. That point will be on the line for your child’s percentile. You can repeat that process for your child’s head circumference as well.

What do the percentiles on a growth chart mean?

Imagine babies on a 100-step staircase. Each step is a percentile. If your baby is on the 78th step from the bottom, she’s higher than 78 percent of all the other babies of the same sex and age.

How do you interpret height and weight trends?

Your doctor is looking at the big picture, especially assessing whether your child’s growth follows a consistent curve that parallels the percentile line. If you think of that line like a lane in traffic, the doctor wants to see your child stay in their lane and follow that swooping curve upward. If there are some “lane shifts” in the weight height chart, it might indicate a health problem.

Should I worry if my child is in a low percentile?

A low percentile in a weight and height chart doesn’t necessarily mean that something is wrong. The doctor is looking at multiple data points, including consistent growth and nutrition. Premature children, for example, might need a specialized chart. The overall pattern is what matters.

If my baby is in a high percentile, will they be overweight?

You can’t really tell if your baby will eventually end up being short, tall, fat, or thin based on their infant growth chart. Starting at about age 2, your child’s body mass index will be included in their assessment, and that can provide some insight about the relationship between your child’s weight and health.

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