3-Month-Old Baby Weight & Length Chart
At 3 months, many babies have doubled their newborn weight or are well on their way. Growth rate starts to slow slightly compared to the first weeks.
Boy — 50th %ile
Girl — 50th %ile
⚖️ Weight by Percentile
| Percentile | 👦 Boy | 👧 Girl |
|---|---|---|
| 5th Percentile | 11 lbs 14 oz | 10 lbs 13 oz |
| 10th Percentile | 12 lbs 6 oz | 11 lbs 0 oz |
| 25th Percentile | 13 lbs 4 oz | 11 lbs 14 oz |
| 50th Percentile (median) | 14 lbs 2 oz | 12 lbs 13 oz |
| 75th Percentile | 14 lbs 16 oz | 13 lbs 11 oz |
| 90th Percentile | 15 lbs 14 oz | 14 lbs 9 oz |
| 95th Percentile | 16 lbs 9 oz | 14 lbs 16 oz |
📏 Length/Height by Percentile
| Percentile | 👦 Boy | 👧 Girl |
|---|---|---|
| 5th Percentile | 1' 11.3" | 1' 10.7" |
| 10th Percentile | 1' 11.5" | 1' 10.9" |
| 25th Percentile | 1' 11.9" | 1' 11.2" |
| 50th Percentile (median) | 2' 0.2" | 1' 11.5" |
| 75th Percentile | 2' 0.5" | 1' 11.9" |
| 90th Percentile | 2' 0.8" | 2' 0.2" |
| 95th Percentile | 2' 1" | 2' 0.4" |
📊 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
- Pushes up on forearms during tummy time
- Laughs and squeals
- Recognizes familiar faces and voices
- Reaches toward objects
This is often called the "golden period" — colic often resolves, babies are more interactive, and sleep patterns start to organize.
🍼 Feeding at 3 Month Old
Breastfed babies may begin feeding slightly less often (7–9 times/day) as feeds become more efficient. Formula: 4–6 oz every 3–4 hours.
🚨 Talk to Your Pediatrician If…
- Not smiling or responding to sounds
- Does not bring objects to mouth
- Can't hold head up
- Doesn't push down when feet placed on firm surface
Frequently Asked Questions
How much should a 3-month-old weigh?
WHO median is 6.4 kg (14.1 lbs) for boys and 5.8 kg (12.8 lbs) for girls. Normal range: roughly 5.4–7.5 kg (11.9–16.5 lbs).
Is the 3-month growth spurt real?
Yes — growth spurts commonly occur around 3 months. Your baby may feed more frequently, seem fussier, and sleep more for a few days.
When do babies start sleeping longer at night?
Many 3-month-olds begin consolidating sleep and may do 4–6 hour stretches, but this varies widely. Sleep training typically isn't recommended until 4–6 months.
Should my 3-month-old be on a schedule?
A loose eat-play-sleep routine (rather than a rigid schedule) works well at this age. Follow hunger cues rather than the clock.