Average Weight for a 20-Month-Old Boy
The average (50th-percentile) weight for a 20-month-old boy is 11.3 kg (25.0 lb), based on the WHO Child Growth Standards. Across the healthy range, most boys this age weighs between 9.2 kg (20.3 lb) and 14.0 kg (30.9 lb).
| Percentile | Metric | Imperial |
|---|---|---|
| 3rd | 9.2 kg | 20.3 lb |
| 15th | 10.1 kg | 22.3 lb |
| 50th | 11.3 kg | 25.0 lb |
| 85th | 12.7 kg | 28.1 lb |
| 97th | 14.0 kg | 30.9 lb |
What's typical at this age
Growth is steady and gradual now. Portion sizes and appetite vary a lot from meal to meal and day to day. Consistency over weeks matters far more than any single weigh-in. Between month 20 and month 21, the median boy gains roughly 202 g.
A percentile compares your boy to other boys the same age — the 50th is simply the middle. Being above or below it is usually completely normal; a baby who has always tracked the 15th or 85th percentile is typically growing exactly as they should. What pediatricians watch for is a sudden change in the pattern, not the number itself.
See your own baby's percentile
Enter your child's exact weight and height for their personal WHO percentile and growth curve.
Open the Growth Calculator →Percentiles calculated from the WHO Child Growth Standards (2006). For information only — not medical advice. If you're concerned about your child's growth, speak to your pediatrician or health visitor. Full disclaimer.