Head circumference percentiles for a newborn girl
For a newborn girl, the WHO median head circumference (50th percentile) is 33.9 cm. Most healthy girls this age measure between 31.7 cm and 36.1 cm, the 3rd and 97th percentiles.
Percentile table
| Percentile | Value | Imperial |
|---|---|---|
| 3rd | 31.7 cm | 12.5 in |
| 5th | 31.9 cm | 12.6 in |
| 15th | 32.7 cm | 12.9 in |
| 25th | 33.1 cm | 13.0 in |
| 50th (median) | 33.9 cm | 13.3 in |
| 75th | 34.7 cm | 13.7 in |
| 85th | 35.1 cm | 13.8 in |
| 95th | 35.8 cm | 14.1 in |
| 97th | 36.1 cm | 14.2 in |
Values from the WHO table, rounded to one decimal.
Source: WHO Child Growth Standards, head circumference-for-age table. Every value on this page is checked automatically against the published WHO table before publishing, and the calculator uses WHO's LMS method. Updated October 2, 2026. Corrections and questions: ahozon@benbasha.com
Percentile calculator
Enter your child's measurement to see the WHO percentile. It uses the same WHO 2006 engine as the Ahozon app, and nothing you type leaves this page.
How growth looks at this age
For comparison, the median for boys of the same age is 34.5 cm.
Head circumference at birth can be affected by the shape of the head after delivery, so the first measurement is less reliable than later ones.
What does the percentile mean?
A percentile compares a child with healthy children of the same age and sex from the WHO Multicentre Growth Reference Study. At the 40th percentile, 40 out of 100 children have a smaller head circumference and 60 a larger one. Anything between the 3rd and 97th percentile is in the normal range. What matters most is that a child keeps following a similar curve over time.
How to measure
Measure with a flexible tape around the widest part of the head, just above the eyebrows and ears. Take the largest of three readings.
When to ask your pediatrician
Talk to your pediatrician or child health nurse if a measurement is below the 3rd or above the 97th percentile, or if your child's percentile changes a lot between visits, for example crossing two of the main percentile lines. A single measurement says little; the trend over time matters most.
General information, not medical advice. One measurement says little on its own: talk to your pediatrician or child health nurse about your child's growth.