Percentiles rank, they don't grade. The most common parent mistake is treating the number like a test score — the real question is whether the curve is steady.
A percentile is a ranking
If your baby is at the 40th percentile, about 40 out of 100 healthy babies of the same age and sex weigh less. It is a position in a crowd, not a pass or fail.
The normal band is wide
The 3rd to 97th percentile is the normal range. Being near the edge is not a problem by itself; what matters is how the curve moves over time.
Read the curve, not the point
A baby who holds their percentile band through the first year is growing predictably. A sudden drop across lines, or a flat line for months, is what deserves a conversation.
GrowChart reads it for you
Enter each weight and GrowChart shows the percentile, the curve, and the trend — no math homework required.
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