Choosing the Right Baby Clothing Sizes by Age
Why the label age is often wrong — and how to size correctly
4 min read
Age labels are only a guide
A "0-3 month" label assumes an average-percentile baby. Larger newborns can skip straight to 3-6 months, while smaller or premature babies may need preemie or newborn sizing for longer than expected.
Size up for growth spurts
Babies can grow an inch in a single week during a growth spurt. When in doubt between two sizes, choose the larger one — a slightly loose onesie is far more comfortable than a tight one.
Check the fabric, not just the size
Stretchy knits (like our Pima cotton range) are more forgiving across growth spurts than structured wovens, buying you extra weeks of wear from a single size.
A practical rule of thumb
Buy the current size in small quantities and the next size up in bulk — by the time your baby fits into it, that’s exactly where they’ll be.
“When shopping ahead, size up rather than sticking to the age on the label — your baby’s actual growth curve is the only size chart that matters.”
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