Estimate weight-for-age and length/height-for-age percentiles for children from birth through 5 years using bundled WHO LMS reference anchors.
A quick decision brief for this specific tool
Child age from birth through 60 completed months, WHO boy/girl reference, weight, and recumbent length or standing height in metric or imperial units
Approximate WHO weight-for-age and length/height-for-age z-scores, percentiles, and reference-line context
Sex-specific bundled WHO LMS anchors with linear age interpolation, LMS z-score calculation, and standard-normal percentile conversion
Choose your path
Estimate WHO weight-for-age and length/height-for-age context for birth through 60 months without presenting a sparse reference or one measurement as a diagnosis.
Place weight and length/height in age- and sex-specific WHO context.
Enter completed years/months, choose the WHO boy/girl reference, and enter both measurements.
Receives finite z-score/percentile estimates and understands they are a screen.
Avoid mixing recumbent length and standing height.
Review the measurement note before entering length under 2 or standing height from age 2.
Repeats the measurement consistently and seeks professional confirmation for surprising results.
Know the reference resolution and age boundary.
Review the WHO-only 0–60 month and bundled-anchor interpolation disclosure.
Does not infer official chart precision, CDC coverage, diagnosis, or trend from one result.
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WHO child growth standards cover ages 0–5. This browser tool uses bundled sex-specific weight-for-age and length/height-for-age LMS anchors and linearly interpolates between available ages.
WHO LMS z-score → standard-normal percentileFormula: WHO Child Growth Standards
The LMS method accounts for age-specific skewness (L), median (M), and variation (S). The resulting z-score is converted to an approximate standard-normal percentile.
Z = ((measurement / M)^L − 1) / (L × S); logarithmic form when L ≈ 0Use recumbent length under age 2 and standing height from age 2. A single estimate is not diagnostic; clinicians interpret accurate serial measurements, health history, and the appropriate chart together.
Supported age = 0–60 completed monthsUpdated: August 2026
A pediatric visit tracks whether a toddler's height and weight fall within expected growth ranges.
→ Two WHO-based screening estimates; verify the measurements and follow the child's trend over time
A caregiver records a measurement for discussion with a pediatric professional, paying attention to the child's serial growth pattern rather than diagnosing from one percentile.
→ An approximate WHO percentile and z-score, with a prompt to seek professional interpretation of unusual or changing patterns
A caregiver compares recumbent length versus standing-height instructions before entering the value, because mixing methods can shift the estimate.
Growth is tracked over time, not single measurements. A child at the 15th percentile is normal if following their curve. Concern arises when percentiles cross downward significantly.
Pediatric growth uses age- and sex-specific percentile charts (WHO/CDC). Adult BMI categories do not apply. Always use pediatric reference charts.
Enter a child's completed age, sex reference, weight, and recumbent length or standing height for a WHO-based screening estimate from birth through 5 years. The bundled reference is interpolated and the result cannot diagnose growth or replace a pediatric growth chart review.