A growth chart looks like spaghetti until someone explains the lines. Here is the five-minute decode that makes it obvious.
The lines are percentiles
Each curve on the chart is a percentile band — 3rd, 15th, 50th, 85th, 97th — showing where children at that rank sit. The middle line is the median, not a target.
The band system
Between the 3rd and 97th is the normal range. Within ±1 SD of the median is where most healthy children sit; ±1 to ±2 is acceptable; beyond ±2 is where doctors pay extra attention.
Steady beats any line
A child tracking any single band is growing predictably. The chart's job is showing whether the path stays steady, climbs gently, or crosses lines suddenly.
Practice on a real chart
GrowChart draws the official WHO bands with your child's measurements on top, so reading your own chart becomes second nature.
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