Reference Guide

Why Tracking Percentiles Over Time Beats Any Single Number

One measurement tells you where a child is. A series of measurements tells you where they are going — and that direction is the real signal.

The point is noise, the curve is signal

A single measurement carries measurement error and day-to-day variation. A curve smooths all that out and shows the underlying pattern.

Direction reveals problems early

Growth problems announce themselves as direction changes — a line that flattens, a drop across bands, a climb that becomes a plateau. These appear only in the series.

Fewer panics, clearer calls

Parents who track the curve stop reacting to single numbers. That steadier view makes checkup conversations clearer and calmer.

GrowChart is built for the series

Every measurement extends the same WHO-standard curve, so the trend — not the latest point — does the talking.

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