When to Size Up: A Parent's Guide to Growth Spurts

Babies and toddlers grow in bursts, not straight lines, so a bodysuit that fits perfectly this week can feel snug within a month. The clearest signs: snaps that strain at the crotch, sleeves that ride up past the wrist, or a neckline that no longer slips over the head with ease.

Our size run is built around age and height rather than age alone, because the two do not always move together. Newborn runs 0–3m at 50–62cm, Baby 3–24m at 62–92cm, Toddler 2–4y at 92–104cm, and Kids 5–10y at 110–140cm — check your child against the height column first if they run tall or small for their age.

If your child sits right between two sizes, size up. A slightly relaxed fit still moves and washes well; a tight one stops being wearable within weeks. We also reinforce the knees from 6 months onward, since that is where crawling and cruising wear through fastest.

Keep the size guide on hand at checkout — it is linked from every product page so you are never guessing between two numbers.