BMI for boys at 2 years
At 2 years, the median BMI for boys on the CDC 2000 growth charts is 16.6 kg/m²: half of boys this age have a lower BMI and half a higher one. The middle half of boys, from the 25th to the 75th percentile, falls between 15.7 and 17.6 kg/m², a spread of 1.8 kg/m². The outer lines of CDC’s BMI-for-age chart, the 5th and 95th percentiles, sit at 14.7 and 19.3 kg/m².
By 3 years it reaches 16.0 kg/m².
For girls at 2 years the median is 16.4 kg/m², 0.2 kg/m² less than for boys, which is why the charts are drawn separately by sex.
CDC uses BMI-for-age, not weight-for-length, from age 2. At 2 years the 85th percentile for boys is 18.2 and the 95th is 19.3 kg/m². Above the 95th percentile, CDC's 2022 extended charts replace the original curve, so the 99th percentile here is 21.1 kg/m², computed with the extended method.
Reading the table: a boy at 2 years with a BMI of 17.0 kg/m² is at about the 62nd percentile, meaning that out of 100 boys this age, about 62 have a lower BMI.
Percentiles at 2 years
Download CSV (all ages)| Percentile | z-score | BMI |
|---|---|---|
| 3rd | −1.88 | 14.5 kg/m² |
| 5th | −1.64 | 14.7 kg/m² |
| 10th | −1.28 | 15.1 kg/m² |
| 25th | −0.67 | 15.7 kg/m² |
| 50th (median) | 0.00 | 16.6 kg/m² |
| 75th | +0.67 | 17.6 kg/m² |
| 85th | +1.04 | 18.2 kg/m² |
| 90th | +1.28 | 18.6 kg/m² |
| 95th | +1.64 | 19.3 kg/m² |
| 97thextended | +1.88 | 20.1 kg/m² |
| 98thextended | +2.05 | 20.5 kg/m² |
| 99thextended | +2.33 | 21.1 kg/m² |
Above the 95th percentile, values use CDC’s 2022 extended BMI-for-age method; z-scores shown are the matching normal z. Values computed with the LMS method from the published tables (retrieved 2026-10-05).