- Average weight at 7 months: girls 16 lb 14 oz (7.6 kg), boys 18 lb 5 oz (8.3 kg), the WHO median or 50th percentile.
- The usual range (3rd to 97th percentile) is 13 lb 7 oz to 21 lb 4 oz for girls and 14 lb 14 oz to 22 lb 6 oz for boys.
- The curve matters more than the number. A baby who keeps following roughly the same line is growing well, wherever that line is.
- Born early? Use the corrected age until 2 years.
What percentile is my 7-month-old?
Type your baby's weight and we'll open the growth percentile calculator set to 7 months, with your baby's percentile, curve and a plain-words verdict. Add the real birth date there for an exact result.
7-month-old girls: weight, length and head percentiles (WHO)
| 3rd | 15th | 50th (average) | 85th | 97th | |
|---|---|---|---|---|---|
| Weight | 13 lb 7 oz 6.1 kg | 14 lb 14 oz 6.7 kg | 16 lb 14 oz 7.6 kg | 19 lb 2 oz 8.7 kg | 21 lb 4 oz 9.6 kg |
| Length | 24¾ in 62.9 cm | 25½ in 64.9 cm | 26½ in 67.3 cm | 27½ in 69.7 cm | 28¼ in 71.6 cm |
| Head | 16 in 40.4 cm | 16¼ in 41.5 cm | 16¾ in 42.8 cm | 17½ in 44.2 cm | 17¾ in 45.3 cm |
7-month-old boys: weight, length and head percentiles (WHO)
| 3rd | 15th | 50th (average) | 85th | 97th | |
|---|---|---|---|---|---|
| Weight | 14 lb 14 oz 6.7 kg | 16 lb 5 oz 7.4 kg | 18 lb 5 oz 8.3 kg | 20 lb 7 oz 9.3 kg | 22 lb 6 oz 10.2 kg |
| Length | 25½ in 65.1 cm | 26¼ in 66.9 cm | 27¼ in 69.2 cm | 28 in 71.4 cm | 28¾ in 73.2 cm |
| Head | 16½ in 41.7 cm | 16¾ in 42.7 cm | 17¼ in 44.0 cm | 17¾ in 45.3 cm | 18¼ in 46.3 cm |
WHO Child Growth Standards 2006, at exactly 7 months (day 213; one month = 30.4375 days). Length is measured lying down until 2 years. The bold column is the median; the 15th to 85th percentiles hold the middle 70% of babies.
What's typical at this age
From about 7 months weight gain slows to around 2¼ oz (65 g) a week. Babies who start rolling, sitting and creeping burn more energy, and some slide down a line for a while. As long as length and head keep their own curves and your baby is feeding well, that is usually just a busier baby.
- Weight gain: about 2¼ oz (65 g) a week at this stage (WHO median).
- Since birth: 2.4 times the birth weight for girls and 2.5 for boys, and about 7¼ in (18 cm) to 7½ in (19 cm) longer.
- Next checkup: the 9-month checkup (AAP Bright Futures schedule).
- Sleep: usually 2–3 naps, with 2 to 3¼ hours awake in between. The nap planner turns that into a day.
How to read the table
A percentile compares your baby with 100 healthy babies of the same age and sex. The 15th percentile for weight means your baby is heavier than 15 of them and lighter than the other 85. It is not a grade: the 50th is the middle of the crowd, not the goal. Look at weight, length and head together; a baby on the 20th for weight and the 20th for length is simply a smaller baby in proportion.
Crossing two or more of the main lines over time, especially downward, is what pediatricians like to look into. The growth calculator tracks that for you: add each checkup and it draws the curve and tells you how many bands it has moved.
Born early?
For a premature baby, compare with babies of the same corrected age, counted from the due date, until about 2 years. A baby born 8 weeks early is compared at 7 months with the 5-month table. The corrected age calculator works it out, and the growth calculator uses it when you add the due date.
Questions
My 7-month-old is on the 90th percentile. Is that a problem?
No. One in ten healthy babies is at or above it, and big babies of tall parents often stay big. The usual range runs up to the 97th percentile, 21 lb 4 oz (9.6 kg) for girls and 22 lb 6 oz (10.2 kg) for boys at 7 months. What your pediatrician watches is the weight-for-length and whether the curve keeps its shape, not the height of the line.
How much should a 7-month-old gain per week?
Around 2¼ oz (65 g) a week is typical at this stage on the WHO standards. Week-to-week numbers jump with feeds, diapers and the scale, so compare over a month. Add two measurements to the growth calculator and it shows your baby's own weekly gain next to the typical one.
How big is the difference between boys and girls at 7 months?
On the WHO medians a boy is about 1 lb 7 oz (650 g) heavier and ¾ in (1.9 cm) longer than a girl. That is why the charts are separate: a girl on the 30th percentile and a boy on the 30th weigh different amounts.
Sources
- World Health Organization, WHO Child Growth Standards (2006): the weight-for-age, length-for-age and head-circumference-for-age tables. The numbers on this page come from the LMS tables in the WHO anthro package.
- CDC, Recommended growth charts (WHO charts from birth to 2, CDC charts from 2).
- American Academy of Pediatrics, Bright Futures periodicity schedule (checkup ages and screenings).
- Paruthi S. et al., Recommended amount of sleep for pediatric populations, American Academy of Sleep Medicine consensus, endorsed by the AAP (J Clin Sleep Med, 2016).
Spotted a mistake or an outdated figure? Write to [email protected].