Baby Onesie Size Chart

Measurement NB 6M 12M 18M 24M
Body Length  10-3/4 11-3/4 12-3/4 13-3/4 14-1/4
Body Length Tolerance 1 1 1 1 1
Chest Tolerance 1/2 1/2 1/2 1/2 1/2
Chest Width (Laid Flat) 7-1/2 9 10 11 12
Sleeve Length 2-1/2 2-3/4 3 3-1/2 3-1/4

Sizing is based on items laid flat for measurement.