Child BMI Chart Calculator

Know your child’s BMI with clear percentiles fast. Compare growth by age, sex, and time. Print charts, share results, and support healthier routines daily.

This tool provides BMI-for-age percentiles for ages 2–20. It is for education, not diagnosis. If you have concerns, consult a pediatric clinician.

Example data

SexAgeHeightWeightBMITypical use
Boy7y 3m128.5 cm28.4 kg17.2School-age growth tracking
Girl12y 0m152.0 cm46.0 kg19.9Pre-teen checkup context
Boy16y 6m173.0 cm68.0 kg22.7Teen monitoring and sports

Formula used

BMI is calculated as:

BMI = weight(kg) ÷ [height(m)]²

Percentile uses the LMS method with age- and sex-specific parameters:

z = ((BMI/M)L − 1) ÷ (L·S)

Percentile ≈ NormalCDF(z) × 100.

How to use this calculator

  1. Choose sex and enter age in years and months.
  2. Select units and enter height and weight.
  3. Press Submit to see BMI, percentile, and the chart.
  4. Download CSV or PDF for records or clinic visits.
  5. Track changes over time, not a single value.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.