9-Month-Old Baby Weight & Length Chart
The 9-month checkup is a big one. Your pediatrician will check development, do a hemoglobin screening for anemia, and assess hearing and vision.
Boy — 50th %ile
Girl — 50th %ile
⚖️ Weight by Percentile
| Percentile | 👦 Boy | 👧 Girl |
|---|---|---|
| 5th Percentile | 16 lbs 9 oz | 15 lbs 3 oz |
| 10th Percentile | 16 lbs 16 oz | 15 lbs 10 oz |
| 25th Percentile | 18 lbs 5 oz | 16 lbs 12 oz |
| 50th Percentile (median) | 19 lbs 10 oz | 18 lbs 1 oz |
| 75th Percentile | 20 lbs 15 oz | 19 lbs 6 oz |
| 90th Percentile | 22 lbs 4 oz | 20 lbs 8 oz |
| 95th Percentile | 22 lbs 15 oz | 21 lbs 3 oz |
📏 Length/Height by Percentile
| Percentile | 👦 Boy | 👧 Girl |
|---|---|---|
| 5th Percentile | 2' 3.4" | 2' 2.6" |
| 10th Percentile | 2' 3.6" | 2' 2.9" |
| 25th Percentile | 2' 4" | 2' 3.2" |
| 50th Percentile (median) | 2' 4.3" | 2' 3.6" |
| 75th Percentile | 2' 4.7" | 2' 4" |
| 90th Percentile | 2' 5.1" | 2' 4.3" |
| 95th Percentile | 2' 5.3" | 2' 4.6" |
📊 What Does My Baby's Percentile Mean?
A baby at the 50th percentile weighs more than 50% of babies the same age. The 25th–75th percentile range is considered average. Any percentile from the 5th to the 95th is medically normal — your baby's growth curve matters more than their rank. A consistently healthy 10th-percentile baby is thriving; a baby who drops from the 70th to the 30th percentile warrants a conversation with your pediatrician.
🌟 Developmental Milestones
- Cruises along furniture
- Uses pincer grasp consistently
- Understands "no"
- Searches for hidden objects (object permanence)
Object permanence is fully established now — your baby knows that things exist even when out of sight. This is why peek-a-boo never gets old.
🍼 Feeding at 9 Month Old
Solids 3x/day with a wide variety of textures. Breast milk or formula: 24–30 oz/day. Introduce a sippy cup with water at meals.
🚨 Talk to Your Pediatrician If…
- Doesn't bear weight on legs
- Doesn't sit without support
- Not babbling
- Doesn't play any back-and-forth games
Frequently Asked Questions
How much should a 9-month-old weigh?
WHO median is 8.9 kg (19.6 lbs) for boys and 8.2 kg (18.1 lbs) for girls. Normal range: roughly 7.5–10.4 kg (16.5–22.9 lbs).
What happens at the 9-month well visit?
Your pediatrician will check growth, assess developmental milestones, screen for iron-deficiency anemia with a blood test, and may do a lead screening depending on your area.
When should my baby start drinking water?
Small amounts of water (2–4 oz/day) can be introduced when solids begin at 6 months. At 9 months, offering water with meals in a sippy cup helps establish the habit.
Is my baby's head too big? (macrocephaly)
Head size follows its own growth curve. Isolated large head size (above 95th percentile) in an otherwise developing baby is often genetic. Your pediatrician will monitor the curve.