When trying to decide between two sizes, choose the larger size for a better fit.
| Size | Chest | Waist | Hips | Height | Weight |
| 0-3 Months | 17.5 | 18.5 | 18 | 24 | 7-12 |
| 3-6 Months | 18 | 18.75 | 18.5 | 26.5 | 12-17 |
| Newborn One Size | 17 1/2-18 | 18 1/2-18 3/4 | 18/-18 1/2 | 26.5 | 7-17 |
| 6-12 Months | 19 | 19.25 | 19.5 | 30' | |
| 12-18 Months | 19.5 | 19.5 | 20 | 32.5 | |
| 18M-2T | 20.5 | 20 | 20.5 | 34.5 | |
| Infant One Size | 19-20 1/2 | 19 1/4-20 | 19 1/2-21 1/2 | 34.5 | |
| *in inches |
