A typical 10-month-old weighs between 16 and 22 pounds, depending on sex and individual growth patterns. Boys tend to be slightly heavier, averaging around 20 pounds, while girls average closer to 18.5 pounds. But the number on the scale matters less than whether your baby is following a consistent growth curve over time.
Average Weight by Sex
According to the WHO growth charts used by most pediatricians, the 50th percentile weight for a 10-month-old boy is about 20.2 pounds (9.2 kg). For girls, it’s about 18.7 pounds (8.5 kg). These are midpoint figures, meaning half of healthy babies weigh more and half weigh less.
The normal range is wide. A boy at the 15th percentile might weigh around 18 pounds, while one at the 85th percentile could be closer to 23 pounds. Both are perfectly healthy. What pediatricians care about is whether your baby stays near the same percentile over several months, not whether they hit one specific number.
Why Growth Curves Matter More Than a Single Number
A single weigh-in is just a snapshot. The real picture comes from plotting your baby’s weight on a growth chart at multiple visits. A baby who has tracked along the 25th percentile since birth is growing exactly as expected, even though they weigh less than a baby on the 75th percentile. Both are thriving.
The concern arises when a baby’s weight starts crossing percentile lines downward. Pediatricians now use the term “faltering weight” instead of the older, more stigmatizing phrase “failure to thrive.” The key red flags include weight dropping below the 5th percentile for age, or a noticeable decline in weight gain velocity compared to what’s expected. A steady slide down the growth chart over two or more visits is what prompts closer evaluation, not a single low reading.
Expected Weight Gain at This Age
Between 10 and 12 months, babies typically gain about 13 ounces per month. That’s noticeably slower than the rapid gains of early infancy, when a newborn might double their birth weight by five months. By 10 months, growth is more gradual, and that’s normal.
One reason for the slowdown: your baby is probably moving a lot more. Crawling, pulling up on furniture, and cruising all burn calories that previously went toward putting on weight. If your baby recently became mobile and their weight gain has tapered slightly, that’s a predictable and healthy shift.
Breastfed vs. Formula-Fed Differences
Breastfed and formula-fed babies grow differently, and this is well documented. Healthy breastfed infants typically gain weight more slowly than formula-fed infants during the first year. Formula-fed babies tend to gain weight faster after about three months of age, and these differences persist even after solid foods are introduced.
Height growth, on the other hand, is similar regardless of feeding method. So a breastfed baby who appears leaner than a formula-fed peer at 10 months is following a normal, expected pattern. The WHO growth charts were designed based primarily on breastfed infants, which is why the CDC recommends using them for all children under two.
Calorie Needs at 10 Months
A 10-month-old needs roughly 750 to 900 calories per day. About 400 to 500 of those calories should still come from breast milk or formula, which works out to around 24 ounces a day. The rest comes from solid foods.
At this age, most babies are eating three meals of soft table foods or purees alongside their milk feeds. The balance gradually shifts toward more solid food over the next few months, but breast milk or formula remains the nutritional backbone through the first birthday. If your baby is eating well at meals but still nursing or taking bottles regularly, their calorie needs are likely being met even if they seem to be gaining weight slowly.
How to Weigh Your Baby at Home
If you want to track your baby’s weight between pediatric visits, digital baby scales give the most accurate reading. Place the scale on a hard, flat surface like a kitchen or bathroom floor, not on carpet. Make sure it reads zero before you set your baby down, and weigh them naked for the most consistent results.
A few tips for reliable measurements: weigh at roughly the same time of day, ideally before a feed. Make sure your baby’s legs aren’t hanging off the edge of the scale. If your baby is squirming, wait for the number to stabilize before recording it. You can lay a light blanket on the scale for comfort, just zero the scale after placing the blanket and before setting your baby down.
If you don’t have a baby scale, you can use regular bathroom scales. Weigh yourself first, then weigh yourself holding your naked baby, and subtract. This method is less precise but gives a reasonable estimate. You can also test your scale’s accuracy with a known weight, like a 1 kg bag of sugar, to make sure it’s reading correctly.
Signs That Weight May Be a Concern
Most babies at 10 months are growing fine, but a few patterns are worth watching for. If your baby’s weight has dropped noticeably on the growth chart over two or more checkups, that’s worth discussing with your pediatrician. Other signs include loss of interest in feeding, consistently refusing both milk and solids, or visible signs like loose skin or loss of fat in the face and limbs.
Keep in mind that short-term dips are common. A bout of illness, teething discomfort, or a developmental leap that disrupts eating can all cause a temporary plateau. These usually resolve on their own within a week or two. The pattern pediatricians look for is sustained, not a single off week.