Baby Clothes Size Finder
Baby clothes are labeled by age, but babies are not — and every brand draws its size chart differently. Enter your baby’s weight and this free tool shows the size most brands’ published charts point to, how much brands disagree at that weight, and which labels run big or small. It reads brands’ own charts; it is not a measurement of your baby.
Baby Clothes Size Finder
Enter your baby’s weight to see the size most brands’ charts point to — and which brands run big or small. Built from 30 brands’ published size charts (September 2026). It reads the brands’ own charts — it is not a measurement of your baby.
At 14 lb, most published charts point to
3-6M
Runs small — size up
Old Navy, Nike, Cat & Jack
Their label maxes out at a lighter weight on paper.Runs big — size down
Patagonia, The Children’s Place, babyGap
Their label covers heavier babies on paper.Powered by Babbez · brand-published charts, Sept 2026 · we did not measure or test any garment.
How the size finder works
We compared the published size charts of 30 baby-clothing brands (26 distinct charts) in September 2026. For any weight, the tool shows the size whose cross-brand median weight range contains it, the full range that weight spans across brands, and which brands’ charts run big or small. Every figure comes from the brands’ own charts — nothing here is estimated, and we did not measure or test any garment.
Why do baby-clothing sizes vary so much?
Because a size label is not standardized. On brands’ published charts the same “3–6M” label tops out anywhere from about 14.5 lb to 20 lb, and “18–24M” from about 26 lb to 32 lb. That is why the same baby can wear two different labels depending on the brand — and why checking the specific brand’s chart beats trusting the label.
This tool is about clothing labels, not your baby’s growth or health. For your baby’s growth and the right time to move up a size, talk to your pediatrician and see the American Academy of Pediatrics. Read our medical disclaimer.
Go deeper
- The Baby Clothing Size Index 2026 — the full 30-brand comparison behind this tool.
- The Sizing-Spread Index — how far the same label stretches across brands.
- What baby clothes really cost the first year — real per-item prices from 23 brands.
Baby and toddler clothing size by weight (30-brand reference)
The finder above gives your baby’s brand-by-brand result. Here is the underlying reference in plain HTML: the typical weight range for each size, and how much the top of that range varies across the 30 brands sold in the US whose published size charts we compared. Data from the Babbez Baby Clothing Size Index (September 2026); the same label is not the same size across brands, so treat these as approximate and buy by your baby’s measurement.
| Size | Typical weight range | Top of range varies (across brands) | Brands giving a weight limit |
|---|---|---|---|
| Preemie | 3–5.5 lb | 5–7 lb (2 lb spread) | 14 |
| Newborn | 6–8 lb | 7–10 lb (3 lb spread) | 24 |
| 0-3M | 8–12 lb | 11–15 lb (4 lb spread) | 24 |
| 3-6M | 12–17 lb | 14.5–20 lb (5.5 lb spread) | 26 |
| 6-9M | 16.5–20 lb | 18–22 lb (4 lb spread) | 20 |
| 9-12M | 20–24 lb | 22–26 lb (4 lb spread) | 17 |
| 12-18M | 22.5–27 lb | 24–28 lb (4 lb spread) | 26 |
| 18-24M | 27–30 lb | 26–32 lb (6 lb spread) | 25 |
| 2T | 28.8–31 lb | 28–33 lb (5 lb spread) | 16 |
| 3T | 31–34 lb | 32–36 lb (4 lb spread) | 18 |
| 4T | 34–38 lb | 36–40 lb (4 lb spread) | 17 |
| 5T | 37.8–42 lb | 41–48 lb (7 lb spread) | 14 |
Brands that tend to run big: Patagonia (baby) (+1.5 lb), The Children's Place (+1.2 lb), Gap (babyGap) (+0.9 lb), Amazon Essentials (baby) (+0.7 lb), Mini Boden (+0.7 lb), Hatley (+0.6 lb).
Brands that tend to run small: Old Navy (-1.5 lb), Nike (infant/toddler) (-1.1 lb), Target Cat & Jack (-1 lb), Primary (-0.7 lb), Target Cloud Island (-0.6 lb), Walmart Garanimals (-0.6 lb), Hanna Andersson (-0.6 lb).
Key findings (free to cite)
- The same '0-3M' label tops out anywhere from 11 lb to 15 lb across 24 brands' published charts — a 4 lb spread.
- The same '3-6M' label tops out anywhere from 14.5 lb to 20 lb across 26 brands' published charts — a 5.5 lb spread.
- The same '6-9M' label tops out anywhere from 18 lb to 22 lb across 20 brands' published charts — a 4 lb spread.
- The same '9-12M' label tops out anywhere from 22 lb to 26 lb across 17 brands' published charts — a 4 lb spread.
- The same '12-18M' label tops out anywhere from 24 lb to 28 lb across 26 brands' published charts — a 4 lb spread.
- The same '18-24M' label tops out anywhere from 26 lb to 32 lb across 25 brands' published charts — a 6 lb spread.
- The same '2T' label tops out anywhere from 28 lb to 33 lb across the 16 brands that publish a 2T weight limit — a 5 lb spread.
Source: Babbez Baby Clothing Size Index, 30 brands sold in the US, September 2026. Sizing information only, not medical or growth advice — see our medical disclaimer.