Baby size guide: how to get it right by age and weight

Why getting the size right changes everything

Babies grow incredibly fast in the first months. Choosing the right size doesn't just avoid exchanges and returns: it also keeps your baby comfortable, free to move and with well-cared-for skin. At Carter's, every garment is designed to accompany each stage, from preemie to 24 months.

Handy size chart

Baby sizes are mainly guided by age and weight. As a general reference:

• Preemie (PRE): up to 2.5 kg
• Newborn (NB): up to 3.5 kg · 0-1 month
• 3 months (3M): 4-6 kg · 1-3 months
• 6 months (6M): 6-8 kg · 3-6 months
• 9 months (9M): 8-9 kg · 6-9 months
• 12 months (12M): 9-11 kg · 9-12 months
• 18 months (18M): 11-12.5 kg · 12-18 months
• 24 months (24M): 12.5-14 kg · 18-24 months

3 tips to get it right

1. Go by weight, not just age. Every baby is unique: two babies of the same age may need different sizes.

2. If in doubt between two sizes, size up. The garment lasts longer and your baby stays comfy.

3. Think about the season. For winter, leave room for an inner layer.

Ready to dress your little one? Discover our newborn essentials and softest bodysuits.