Head circumference for girls at 2 years
At 2 years, the median head circumference for girls on the CDC 2000 growth charts is 47.5 cm (18.7 in): half of girls this age measure less and half more. The middle half of girls, from the 25th to the 75th percentile, falls between 46.5 and 48.4 cm, a spread of 1.9 cm. The outer lines of the chart, the 3rd and 97th percentiles, sit at 44.8 and 50.0 cm.
Since 23 months, the median has risen by 0.4 cm in one month. By 3 years it reaches 48.6 cm.
For boys at 2 years the median is 48.7 cm, 1.2 cm more than for girls, which is why the charts are drawn separately by sex.
From 2 years, head circumference is read on the CDC 2000 infant charts, which run to 36 months; CDC draws the 3rd to the 97th percentile.
Reading the table: a girl at 2 years who measures 48.0 cm is at about the 65th percentile, meaning that out of 100 girls this age, about 65 measure less.
Percentiles at 2 years
Download CSV (all ages)| Percentile | z-score | Metric | Imperial |
|---|---|---|---|
| 3rd | −1.88 | 44.8 cm | 17.6 in |
| 5th | −1.64 | 45.1 cm | 17.8 in |
| 10th | −1.28 | 45.7 cm | 18.0 in |
| 25th | −0.67 | 46.5 cm | 18.3 in |
| 50th (median) | 0.00 | 47.5 cm | 18.7 in |
| 75th | +0.67 | 48.4 cm | 19.1 in |
| 90th | +1.28 | 49.2 cm | 19.4 in |
| 95th | +1.64 | 49.7 cm | 19.6 in |
| 97th | +1.88 | 50.0 cm | 19.7 in |
CDC 2000 charts draw the 3rd to the 97th percentile. Values computed with the LMS method from the published tables (retrieved 2026-10-05).