Baby weight chart by month
Average baby weight for boys and girls from birth to 24 months, with the normal range on the WHO growth standards that US paediatricians use under age 2.
| Age | Boys | Girls | ||
|---|---|---|---|---|
| Average (50th) | Normal range (3rd–97th) | Average (50th) | Normal range (3rd–97th) | |
| Birth | 7 lb 6 oz | 5 lb 8 oz – 9 lb 9 oz | 7 lb 2 oz | 5 lb 6 oz – 9 lb 3 oz |
| 1 month | 9 lb 13 oz | 7 lb 9 oz – 12 lb 9 oz | 9 lb 3 oz | 7 lb 1 oz – 11 lb 13 oz |
| 2 months | 12 lb 4 oz | 9 lb 11 oz – 15 lb 7 oz | 11 lb 5 oz | 8 lb 13 oz – 14 lb 6 oz |
| 3 months | 14 lb 1 oz | 11 lb 3 oz – 17 lb 7 oz | 12 lb 14 oz | 10 lb 2 oz – 16 lb 5 oz |
| 4 months | 15 lb 7 oz | 12 lb 7 oz – 19 lb 1 oz | 14 lb 3 oz | 11 lb 4 oz – 17 lb 14 oz |
| 5 months | 16 lb 9 oz | 13 lb 6 oz – 20 lb 5 oz | 15 lb 3 oz | 12 lb 1 oz – 19 lb 3 oz |
| 6 months | 17 lb 8 oz | 14 lb 3 oz – 21 lb 7 oz | 16 lb 2 oz | 12 lb 13 oz – 20 lb 5 oz |
| 7 months | 18 lb 5 oz | 14 lb 14 oz – 22 lb 6 oz | 16 lb 14 oz | 13 lb 7 oz – 21 lb 4 oz |
| 8 months | 19 lb 0 oz | 15 lb 7 oz – 23 lb 4 oz | 17 lb 9 oz | 14 lb 0 oz – 22 lb 2 oz |
| 9 months | 19 lb 10 oz | 15 lb 15 oz – 24 lb 1 oz | 18 lb 2 oz | 14 lb 8 oz – 22 lb 14 oz |
| 10 months | 20 lb 3 oz | 16 lb 7 oz – 24 lb 12 oz | 18 lb 11 oz | 14 lb 15 oz – 23 lb 10 oz |
| 11 months | 20 lb 12 oz | 16 lb 14 oz – 25 lb 7 oz | 19 lb 4 oz | 15 lb 6 oz – 24 lb 5 oz |
| 12 months | 21 lb 4 oz | 17 lb 5 oz – 26 lb 1 oz | 19 lb 12 oz | 15 lb 12 oz – 25 lb 0 oz |
| 15 months | 22 lb 12 oz | 18 lb 8 oz – 27 lb 15 oz | 21 lb 3 oz | 16 lb 14 oz – 26 lb 14 oz |
| 18 months | 24 lb 2 oz | 19 lb 9 oz – 29 lb 11 oz | 22 lb 9 oz | 18 lb 0 oz – 28 lb 10 oz |
| 21 months | 25 lb 7 oz | 20 lb 10 oz – 31 lb 7 oz | 23 lb 15 oz | 19 lb 2 oz – 30 lb 7 oz |
| 24 months | 26 lb 13 oz | 21 lb 10 oz – 33 lb 4 oz | 25 lb 5 oz | 20 lb 3 oz – 32 lb 4 oz |
Computed from the WHO Child Growth Standards (2006) weight-for-age LMS tables. Month = completed months of age.
How to use this chart
The average is the 50th percentile: half of healthy babies weigh more, half less. A baby below or above the average is not underweight or overweight; doctors look at whether your baby is following a similar curve over time. To see your baby's exact percentile and plot it on the curve, use the baby weight percentile calculator. Length and head tables are on the WHO growth chart page; for children over 2, see the CDC growth chart.
Weight gain is fastest in the first 3 months and slows through the first year. If you are wondering whether feeds are enough, the baby feeding chart by age shows typical amounts.
Frequently asked questions
What is the average baby weight by month?
On the WHO standards the median (50th percentile) weight is about 7 lb 6 oz for boys and 7 lb 2 oz for girls at birth, 17 lb 8 oz and 16 lb 2 oz at 6 months, and 21 lb 4 oz and 19 lb 12 oz at 12 months. The full month-by-month table is above.
What is the average weight of a 6 month old?
About 17 lb 8 oz (7.9 kg) for boys and 16 lb 2 oz (7.3 kg) for girls at the 50th percentile. The healthy range (3rd to 97th percentile) runs from about 12 lb 13 oz to 21 lb 7 oz.
How much weight should a baby gain each week?
Median WHO growth works out to roughly 221 g (about 8 oz) a week from 2 weeks to 3 months, 115 g a week from 3 to 6 months, and 64 g a week from 6 to 12 months. Most babies lose up to 7–10% of birth weight in the first days and regain it by about 2 weeks.
When do babies double and triple their birth weight?
Most babies roughly double their birth weight by 4–5 months and triple it by about 12 months.
Is my baby's weight normal?
Anywhere from the 3rd to the 97th percentile is considered normal on the WHO charts. Following a steady curve matters more than the exact number. Enter your baby's weight in the weight percentile calculator to see where they sit.
Source: WHO Child Growth Standards: weight-for-age, birth to 5 years (2006). The CDC and AAP recommend the WHO charts for all US children under 2.