Cloud Island Baby Size Chart — Fit by Weight & Height
The Cloud Island baby-clothing size chart, size by size — the weight and height each label covers, and how Cloud Island 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, Cloud Island sizes cover about 0.6 lb less than the Size Index median on average, across 8 sizes. If your baby is near the top of a weight range, size up in Cloud Island.
Cloud Island baby size chart (weight & height)
| Size | Fits weight | Height | Size Index median | Cloud Island vs median |
|---|---|---|---|---|
| Preemie | up to 5.5 lb | up to 17.5 in | 5.5 lb | 0 |
| Newborn | 6–8.5 lb | 18–20 in | 8 lb | +0.5 lb |
| 0-3M | 9–12 lb | 20.5–23.5 in | 12 lb | 0 |
| 3-6M | 12.5–16 lb | 24–25.5 in | 17 lb | −1 lb |
| 6-9M | 16.5–19.5 lb | 26–27.5 in | 20 lb | −0.5 lb |
| 9-12M | 20–23 lb | 28–30.5 in | 23.5 lb | −0.5 lb |
| 18M | 23.5–26 lb | 31–32.5 in | 27 lb | −1 lb |
| 24M | 26.5–28 lb | 33–35.5 in | 30 lb | −2 lb |
Read the “vs median” column to see where Cloud Island differs: a positive number means that size covers heavier babies than the typical brand (runs bigger on paper); negative means smaller. Compared across 8 matching sizes.
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 Cloud Island published size chart and compares each size to the Size Index median for that size, taken across 15 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.