Baby Weight Percentile
Check if your baby's weight and height are on track using WHO growth charts.
Weight Percentile
28.4th
Normal
WHO median (6 mo, male): 7.9 kg
Your baby is at the 28th percentile for weight.
Height Percentile
56.9th
Normal
WHO median (6 mo, male): 67.6 cm
Your baby is at the 57th percentile for height.
Percentile Guide
< 3rd
Very Low
3rd – 15th
Low
15th – 85th
Normal
85th – 97th
High
> 97th
Very High
Note: Consult your pediatrician. Single measurements are less meaningful than growth trends. These calculations use simplified WHO growth-chart approximations and are for informational purposes only.
About Baby Weight Percentile
This tool calculates your baby's weight and height percentiles using WHO (World Health Organization) growth charts for ages 0–24 months. Percentiles show how your baby's measurements compare to a reference population of healthy children of the same age and sex. A result at the 50th percentile means your baby is exactly at the median. Values between the 15th and 85th percentile are generally considered within the normal range, though your pediatrician is always the best judge of healthy growth for your individual child. Growth trends over time matter far more than any single measurement.
Built and maintained by Meet Shah · Last updated
What this tool is used for
- Placing a weight or height on a WHO growth chart percentile.
- Tracking a percentile across several visits rather than one reading.
- Understanding what a percentile figure actually means.
- Comparing a measurement against the reference for that exact age.
- Getting a figure to discuss at an appointment.
Frequently Asked Questions
- What does a percentile actually mean?
- The share of the reference population below that measurement. A baby on the 40th centile is heavier than 40% of babies the same age and sex — which is a description of where they sit, not a score. The 50th is not a target.
- Which growth chart is this?
- The WHO standard, which describes how healthy, breastfed children in optimal conditions GROW rather than how a given population happens to grow. That is why it differs from the older CDC reference, and why the WHO charts are recommended under two years.
- Should I worry about a low percentile?
- Not by itself. A consistently 10th-centile baby who tracks along that line is growing normally; a baby crossing two major centile lines downward is the pattern clinicians actually look for. The trajectory matters far more than the number.
- Why do the charts differ for boys and girls?
- Because growth genuinely differs by sex from birth — boys are on average slightly heavier and longer. Using one chart for both would misclassify a substantial fraction of each, which is why every growth reference is sex-specific.
- Is this a substitute for a clinical assessment?
- No. It interpolates between published reference points and is useful for understanding a number you were given, not for producing one. Growth concerns need a professional with the full history — including birth weight, gestational age and feeding.
Common errors and gotchas
- Reading a low or high percentile as a problem, when the trend over time matters far more than the position.
- Using the wrong reference chart, since WHO and national charts differ.
- Getting the age in weeks or months wrong, which shifts the percentile substantially.
- Comparing a percentile from a different chart to an earlier one.
- Treating the figure as a diagnosis rather than one input for a clinician.