Growth chart: Baby weight and height percentile calculator

Our growth percentile calculator shows how your baby's size compares with other boys or girls the same age. Just enter your child's weight, height (aka length), and head circumference, and we'll calculate a percentile for each. The number reflects what percentage of kids is larger or smaller than your baby. So if your 3-month-old baby is in the 40th percentile for weight, that means 40 percent of 3-month-old babies weigh less than your baby, and 60 percent weigh more.

Using our baby growth chart

When your baby is first born, you'll have several visits at your pediatrician's office to make sure your baby's growth is on track. Your pediatrician will plot your baby's weight, height, and head circumference on a growth chart.

Don't be concerned if your baby doesn't fall right in the middle of the growth chart, though. There's a wide range of normal, and your baby's measurements now don't necessarily reflect what size they'll be as an adult. It's normal for some children to be in the 10th percentile for weight, while other children are in the 90th percentile. The most important thing is that your baby is growing at a healthy and consistent rate, no matter what percentile they're in.

Our growth percentile calculator is a general educational tool only. It's not the last word on how your child is growing, and it's not a substitute for having a healthcare provider monitor your child's growth at regularly scheduled exams. At these visits, your provider will determine whether your child is following a healthy growth pattern over time.

This tool is for children under age 2 and is based on World Health Organization data for kids in that age group. And if you'd like, you can find out how tall your older child is likely to be with our Child Height Predictor.

Read on to learn more about the measurements healthcare professionals take, and learn how to measure your baby at home.

Baby weight

If you want to see how your baby is growing between doctor visits, here's how to get a fairly accurate weight at home:

• Undress your baby completely (remove their diaper, too) and step on a scale while you're holding them. Record that weight.
• Then, set your baby down and weigh yourself. Subtract your own weight from your combined weight with your baby and record that number.
• This isn't as accurate as weighing your baby at the doctor's office, but it's a good estimate of how much your baby weighs.
• If you're worried about your baby's weight gain, call your baby's pediatrician. They may have you come in for a visit, since it's important to have your baby weighed on a consistent scale that can accurately measure weight in pounds and ounces.

Baby height

Before your baby can stand and walk on their own, their height is often recorded as their "length" – that is, how long they are from the crown of their head to the bottom of their heel while lying down. If you want to measure your baby's length at home between doctor visits, here's how:

• Lay your baby down on a flat surface and stretch a measuring tape from the top of their head to the bottom of their heel. Since babies' knees naturally bend a bit, you may need a second person to stretch out their legs while you take the measurement.
• Record their length to the nearest tenth of a centimeter or inch. (In the hospital, birth length is often recorded in centimeters, but your pediatrician's office will likely record their length in inches. What you do is up to you!) Your record might be a little different than the doctor's, but that's okay.

Baby head circumference

Your baby's healthcare provider will measure their head circumference for the first two years of their life to make sure your baby's brain is growing at a healthy rate.

You can measure your baby's head circumference at home, but it can be hard to do this accurately. Here's how to get a good estimate:

• Wrap a flexible measuring tape around the widest part of your baby's head, just above the eyebrows and ears and around the back where their head slopes out from their neck.
• Take the measurement three times (your baby may be wiggly, which could make getting an accurate measurement tough) and use the largest measurement to the nearest 0.1 centimeter.