babyGap Baby Size Chart — Fit by Weight & Height
The babyGap baby-clothing size chart, size by size — the weight and height each label covers, and how babyGap compares with the Size Index median for each size (taken across the distinct brand charts that print a weight for it). Based on the brand’s own published chart (retrieved 2026-09-02); we compare published charts and do not handle or test any garment.
Across its published chart, each babyGap size covers about 1.0 lb more weight (0.95 lb before rounding) than the Size Index median, averaged across 10 sizes in our Size Index. If your baby is between two sizes, you can usually stay in the smaller babyGap size a little longer.
babyGap baby size chart (weight & height)
| Size | Fits weight | Height | Size Index median | babyGap vs median |
|---|---|---|---|---|
| Up to 7 lbs | up to 7 lb | up to 18 in | 8 lb | −1 lb |
| 0 - 3 mos | 7–12 lb | 18–23 in | 12 lb | 0 |
| 3 - 6 mos | 12–17 lb | 23–27 in | 17 lb | 0 |
| 6 - 12 mos | 17–22 lb | 27–29 in | 22 lb | 0 |
| 12 - 18 mos | 22–27 lb | 29–31 in | 27 lb | 0 |
| 18 - 24 mos | 27–30 lb | 31–33 in | 30 lb | 0 |
| 2 yrs | 30–33 lb | 33–36 in | 30.5 lb | +2.5 lb |
| 3 yrs | 33–36 lb | 36–39 in | 34 lb | +2 lb |
| 4 yrs | 36–40 lb | 39–42 in | 38 lb | +2 lb |
| 5 yrs | 40–46 lb | 42–45 in | 42 lb | +4 lb |
Read the “vs median” column to see where babyGap differs: a positive number means that size covers heavier babies than the typical brand (runs bigger on paper); negative means smaller. Compared across all 10 sizes, as in our Size Index; the “Up to 7 lbs” row is compared with the Newborn median.
How we built this
There is no US standard for baby-clothing sizes, so the same label fits different weights at different brands. This page reproduces the babyGap published size chart and compares each size to the Size Index median for that size, taken across 12 to 27 distinct brand charts depending on the size, from our 30-brand Baby Clothing Size Index 2026. Figures are from the brand’s published chart (retrieved 2026-09-02); we compare published charts only and never claim to have measured or tested a garment. For clothing fit only — not a guide to how much a baby should weigh.