What does a baby's growth percentile mean?

A baby's growth percentile tells you how their measurements compare to other babies of the same age and sex. For example, a baby at the 50th percentile for weight means they weigh more than 50% of babies their age. Percentiles ranging from 3rd to 97th are generally considered normal by the WHO.

Is my baby underweight if they are below the 25th percentile?

Not necessarily. A baby consistently tracking along any percentile curve — whether 10th or 90th — is usually healthy. Concern arises when a baby crosses two or more major percentile lines downward over time, which may indicate a growth problem. Always consult your paediatrician.

What is the difference between WHO and CDC growth charts?

WHO charts (used for children 0–2 years) describe how healthy children should grow under ideal conditions, including breastfeeding. CDC charts describe how children in a reference population actually grew. The AAP recommends using WHO charts for children under 2 and CDC charts for children 2 and older.

How often should I track my baby's growth?

Most paediatricians recommend tracking growth at every well-child visit — typically at birth, 1, 2, 4, 6, 9, 12, 15, 18, and 24 months. Using our free tracker between visits helps you spot trends early and bring meaningful data to appointments.

What is adjusted age for premature babies?

Adjusted age (also called corrected age) accounts for prematurity by subtracting the weeks born early from the chronological age. For example, a baby born 8 weeks early who is 6 months old has an adjusted age of 4 months. Growth should be plotted using adjusted age until about 2 years old.

WHO Growth Standards

Growth &
Percentile Tracker

"See exactly how your baby is growing. Real-time percentile calculation based on World Health Organization child growth standards."

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Understanding Growth Percentiles

"A percentile is a ranking, not a grade. Being 'average' is perfectly normal."

Is the 50th Percentile "The Best"?

Technically, the 50th percentile is the exact median weight or height for the global population of babies that age. However, health isn't defined by being exactly in the middle. Anywhere between the 3rd and 97th percentile is generally considered the "healthy range" by pediatricians.

When Should I Worry?

Usually, doctors aren't worried about the absolute number, but rather the **trend**. If a baby starts in the 70th percentile and suddenly drops to the 10th, that's a flag. If they consistently stay in the 10th percentile, they may simply be naturally smaller.

WHO Growth Milestones

3 Months

"Baby should typically double their birth weight by 4-5 months."

6 Months

"Growth slows down slightly as activity levels increase and solids start."

12 Months

"Expect baby to be triple their birth weight and roughly 50% longer than birth length."

24 Months

"Average weight is around 12-13kg for boys and 11-12kg for girls."

Growth & Percentile Tracker