Baby Growth Tracker

Record weight, length or height and head size, with WHO reference comparisons where supported.

Discuss growth with your health visitor, nurse or doctor. A reference comparison is not a diagnosis.

Loading the tool…

What this can tell you

Plot raw measurements by age.
Show WHO weight-for-age and length/height-for-age z-scores and percentiles (birth to under 5, term babies).

What it cannot tell you

Generic reference curves may not suit every baby or condition. Preterm babies need clinician charts. Head circumference and weight-for-length percentiles are not yet provided.

How this is calculated

Uses the official WHO Child Growth Standards expanded daily LMS tables. z = ((x/M)^L − 1)/(L×S); WHO’s restricted method is used for weight beyond ±3. Standing height before 2 years has 0.7 cm added; lying length from 2 years has 0.7 cm subtracted (WHO method). Percentile = normal CDF of z.

Sources

WHO Child Growth Standards – standards and expanded tables – World Health Organization, International; Expanded z-score tables (weight-for-age; length/height-for-age, boys and girls) downloaded 19 Oct 2026; SHA-256 in data/who-manifest.json. Checked 19 October 2026. Opens in a new tab.
WHO Child Growth Standards – software and methods – World Health Organization, International. Checked 19 October 2026 (official entry point). Opens in a new tab.

Group: Baby care & recovery. Responsible: InfantXmore editorial team (not a clinical review). No clinician endorsement is claimed.

Your data

Entries stay in this browser. Session-only mode is the default; choose “Save on this device” to keep them. Manage, export or delete everything in My records. Share this tool with the link only – never your entries.

← Back to all Health Tools · Return to the InfantXmore website