⚖️Baby Weight Percentile (2026)
A baby weight percentile compares your little one's weight to other babies of the same age and sex. If your baby is in the 60th percentile for weight, that simply means they weigh more than about 60 out of 100 babies their age — and less than 40. It is a position on a curve, not a grade. Both WHO and CDC reference charts are available for comparison.
How to read it
Pediatricians care far more about a steady trend than a single number. A baby who has tracked along the 25th percentile since birth is usually doing great. What gets a doctor's attention is a sudden jump or drop across several percentile lines, which is worth a conversation with your pediatrician. Weight gain in the first year averages 150-200g per week in the first 3 months, slowing after 6 months.
Average weight by age (reference, 50th percentile)
| Age | Boys (50th) | Girls (50th) |
|---|---|---|
| Newborn (0 months) | 7.3 lb · 3.3 kg | 7.1 lb · 3.2 kg |
| 6 months | 17.4 lb · 7.9 kg | 16.1 lb · 7.3 kg |
| 12 months | 21.2 lb · 9.6 kg | 19.6 lb · 8.9 kg |
| 18 months | 24.0 lb · 10.9 kg | 22.5 lb · 10.2 kg |
| 24 months | 26.9 lb · 12.2 kg | 25.4 lb · 11.5 kg |
Weights are shown in both kilograms and pounds. WHO charts are based on healthy, breastfed babies worldwide. CDC charts are based on a US reference population including both breastfed and formula-fed babies. See full month-by-month tables on each age page.
Frequently asked questions
What is a baby weight percentile?
A baby weight percentile compares your little one's weight to other babies of the same age and sex. If your baby is in the 60th percentile for weight, that simply means they weigh more than about 60 out of 100 babies their age — and less than 40. It is a position on a curve, not a grade. Both WHO and CDC reference charts are available for comparison.
Is a high or low baby weight percentile a problem?
Not by itself. Pediatricians care far more about a steady trend than a single number. A baby who has tracked along the 25th percentile since birth is usually doing great. What gets a doctor's attention is a sudden jump or drop across several percentile lines, which is worth a conversation with your pediatrician. Weight gain in the first year averages 150-200g per week in the first 3 months, slowing after 6 months. BabyPercent is educational only, not medical advice — your pediatrician is the right person to interpret any measurement.
How is baby weight percentile measured?
Weights are shown in both kilograms and pounds. WHO charts are based on healthy, breastfed babies worldwide. CDC charts are based on a US reference population including both breastfed and formula-fed babies.
WHO vs CDC: which chart should I use?
The WHO charts are recommended by the CDC and AAP for ages 0-24 months. They are based on healthy, breastfed babies from six countries. CDC charts represent a US reference population. BabyPercent provides both so you can compare — your pediatrician probably uses WHO for babies under 2.
How often should my baby be weighed and measured?
The AAP recommends well-baby visits at 3-5 days, 1 month, 2 months, 4 months, 6 months, 9 months, 12 months, 15 months, 18 months, and 24 months. At each visit, your pediatrician measures weight, length, and head circumference. Avoid weighing at home daily — weekly or monthly is plenty.
What is catch-up growth?
Catch-up growth is faster-than-average growth that happens when a baby recovers from a period of slower growth — for example, after an illness or after a premature baby adjusts to life outside the womb. It is a normal compensatory mechanism. Your pediatrician watches for it and will tell you if it is happening as expected.
Does birth weight predict future size?
Not reliably. Birth weight is heavily influenced by in-utero factors like maternal nutrition, gestational age, and placental function. By age 2, a child's growth tends to align more with their genetic potential (parental heights). A small newborn can become a tall adult, and a large newborn can settle into a lower percentile by toddlerhood.
Can growth charts predict my child's adult height?
Roughly, yes — doubling a child's height at 24 months gives a ballpark estimate of adult height, but this is imprecise. Genetics, nutrition, and health all influence final height. Growth charts track the journey, not the destination.