Size Guide

Size guide

Our onesies are designed to fit true to size with a comfortable, non-restrictive cut. If your baby is between sizes or on the heavier side for their age, we recommend sizing up.

Size chart

Size Age (approx.) Weight (kg)
Newborn 0–1 month 2.5–4.5 kg
0–3M 0–3 months 4.5–6.5 kg
3–6M 3–6 months 6.5–8.5 kg
6–9M 6–9 months 8.5–9.5 kg
9–12M 9–12 months 9.5–11 kg
12–18M 12–18 months 11–13 kg
18–24M 18–24 months 13–15 kg

Tips

  • Our onesies are cut generously — they should feel comfortable, not tight.
  • The bamboo spandex blend has natural stretch, so it accommodates a slightly wider size range.
  • If your baby is growing fast, sizing up means more wear time.
  • Still unsure? Email us at hello@gooseymoo.com and we will help you find the right size.