1-Year-Old Baby Weight & Length Chart
Happy first birthday! Most babies have tripled their birth weight by now. The 12-month well visit includes important vaccinations and developmental screening.
Boy — 50th %ile
Girl — 50th %ile
⚖️ Weight by Percentile
| Percentile | 👦 Boy | 👧 Girl |
|---|---|---|
| 5th Percentile | 17 lbs 14 oz | 16 lbs 9 oz |
| 10th Percentile | 18 lbs 8 oz | 16 lbs 16 oz |
| 25th Percentile | 19 lbs 10 oz | 18 lbs 5 oz |
| 50th Percentile (median) | 21 lbs 3 oz | 19 lbs 10 oz |
| 75th Percentile | 22 lbs 11 oz | 20 lbs 15 oz |
| 90th Percentile | 23 lbs 13 oz | 22 lbs 4 oz |
| 95th Percentile | 24 lbs 11 oz | 22 lbs 15 oz |
📏 Length/Height by Percentile
| Percentile | 👦 Boy | 👧 Girl |
|---|---|---|
| 5th Percentile | 2' 4.8" | 2' 4.1" |
| 10th Percentile | 2' 5" | 2' 4.4" |
| 25th Percentile | 2' 5.4" | 2' 4.7" |
| 50th Percentile (median) | 2' 5.8" | 2' 5.1" |
| 75th Percentile | 2' 6.2" | 2' 5.5" |
| 90th Percentile | 2' 6.6" | 2' 5.9" |
| 95th Percentile | 2' 6.8" | 2' 6.2" |
📊 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
- Takes first independent steps (or walking
- Says 2–5 words meaningfully
- Uses objects correctly (drinks from cup, uses spoon)
- Points to show interest
Birth weight typically triples by 12 months. Height will be approximately 1.5× birth length. Growth slows significantly in year 2 — this is normal.
🍼 Feeding at 12 Month Old (1 Year)
Transition from formula to whole cow's milk (16–20 oz/day). Breast milk can continue as long as mutually desired. Avoid honey until 12 months is past. Three meals + 2 snacks.
🚨 Talk to Your Pediatrician If…
- Not standing with support
- No words
- Not using gestures (pointing, waving)
- Doesn't search for hidden objects
- Has lost skills
Frequently Asked Questions
How much should a 1-year-old weigh?
WHO median is 9.6 kg (21.2 lbs) for boys and 8.9 kg (19.6 lbs) for girls. Healthy range: roughly 8.1–11.2 kg (17.9–24.7 lbs).
When should I switch to whole milk?
At 12 months, transition from formula to whole cow's milk (not skim or 2%). Limit to 16–20 oz/day to avoid displacing solid food nutrition.
Why does growth slow down after 12 months?
Infancy is the fastest growth period in a human's life outside the womb. After 12 months, growth rate naturally slows. This can reduce appetite — a 1-year-old eating less than before is typically normal.
My baby isn't walking at 12 months — should I worry?
The normal walking range is 9–15 months. Many healthy babies don't walk until 13–14 months. Mention it at the 12-month visit; your pediatrician will follow up at 15 months if needed.