Reference Guide

The Complete Baby Measurement Guide — Weight, Length, Head

Reliable home measurements turn a growth chart into a useful tool. These are the habits that make each number count.

Weight

Use a baby scale on a hard, level surface. Weigh the baby naked or in a dry diaper. If using the subtraction method — hold the baby and subtract your own weight — use the same clothes both times.

Length

Measure length lying down until about age two. Two people, a firm surface, a straight leg, and a clear heel mark. After two, use a wall-mounted height measure.

Head circumference

Wrap the tape around the widest part of the head — just above the eyebrows and ears, around the back bump. Snug but not tight, in centimeters.

Three habits for reliable numbers

Same person, same tool, same time of day. Log it right away. GrowChart does the charting and the flagging from there.

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