Weight for boys at 19 months
At 19 months, the median weight for boys on the WHO Child Growth Standards is 11.1 kg (24 lb 9 oz): half of boys this age weigh less and half more. The middle half of boys, from the 25th to the 75th percentile, falls between 10.3 and 12.0 kg, a spread of 1.68 kg. The outer lines of the chart, the 2nd and 98th percentiles, sit at 8.91 and 13.9 kg.
Since 18 months, the median has risen by 0.20 kg in one month. By 20 months it reaches 11.3 kg. That monthly change is less than half the 1.12 kg of the first month, because growth slows steadily through the first two years.
For girls at 19 months the median is 10.4 kg, 0.70 kg less than for boys, which is why the charts are drawn separately by sex.
On the older CDC 2000 infant charts, which some clinics and websites still use before age 2, the median at 19 months is 11.9 kg. A boy exactly on the WHO median would read as about the 27th percentile there, one reason two charts can give different answers for the same weight.
Reading the table: a boy at 19 months who weighs 11.7 kg is at about the 67th percentile, meaning that out of 100 boys this age, about 67 weigh less.
Percentiles at 19 months
Download CSV (all ages)| Percentile | z-score | Metric | Imperial |
|---|---|---|---|
| 2nd | −2.00 | 8.91 kg | 19 lb 10 oz |
| 5th | −1.64 | 9.27 kg | 20 lb 7 oz |
| 10th | −1.28 | 9.66 kg | 21 lb 5 oz |
| 25th | −0.67 | 10.33 kg | 22 lb 13 oz |
| 50th (median) | 0.00 | 11.14 kg | 24 lb 9 oz |
| 75th | +0.67 | 12.01 kg | 26 lb 8 oz |
| 90th | +1.28 | 12.85 kg | 28 lb 5 oz |
| 95th | +1.64 | 13.39 kg | 29 lb 8 oz |
| 98th | +2.00 | 13.93 kg | 30 lb 11 oz |
WHO charts label z = ±2 as the 2nd and 98th percentiles (exactly 2.3rd and 97.7th), the cutoffs CDC recommends on WHO charts. Values computed with the LMS method from the published tables (retrieved 2026-10-05).