See roughly where your baby's weight falls compared to other babies the same age, based on WHO growth standards. For an exact reading with length and head circumference too, your pediatrician's chart is always the authoritative source.
This is an approximation based on WHO median growth curves. Your pediatrician's chart accounts for your baby's specific growth history and is always more precise.
A weight-for-age percentile compares your baby to a reference population of babies the same age and sex. A baby at the 60th percentile weighs more than roughly 60% of babies their age — it's a relative comparison, not a grade. The 50th percentile is the median, not a "correct" target.
A single percentile number matters far less than the trend over time. A baby who's consistently tracked around the 20th percentile since birth is likely growing exactly as they should — for them. What pediatricians watch for is a sudden, significant jump across percentile lines in either direction, which can (though doesn't always) signal something worth a closer look.
The WHO charts (used here) are based on breastfed infants from multiple countries and are recommended for children under 2. The CDC charts, used more often for children over 2, are based on a US reference population. Your pediatrician will typically use whichever is standard for your baby's age.
A modest shift like this is common and often not a concern, especially around growth spurts or after starting solids. A sharp, sustained drop across two or more major percentile lines is what typically prompts a pediatrician to investigate further.
Log every weight, length, and head circumference check — BabyQuil plots your baby's personal growth curve over time.
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