Compare calculators

Both calculators run independently — change the inputs on either side to compare results.

Head Circumference Percentile Calculator

Plots a child's head circumference against age-based growth norms to return a percentile. Used by pediatricians to screen for microcephaly, macrocephaly, and hydrocephalus.

Head Circumference (cm)

Age (months)

Fill in the required fields to see your result.

Pediatrics

Pediatric BMI Percentile Calculator

Determines where a child's BMI falls on CDC growth charts for ages 2–20. Use it at well-child visits or when a pediatrician asks you to track healthy weight trends over time.

Child's Age (years)

Weight (lbs)

Height (inches)

Fill in the required fields to see your result.

Key differences

	Head Circumference Percentile Calculator	Pediatric BMI Percentile Calculator
Category	Pediatrics	Pediatrics
Inputs required	2	3
Result	Percentile (%)	BMI Percentile (percentile)
What it does	Plots a child's head circumference against age-based growth norms to return a percentile. Used by pediatricians to screen for microcephaly, macrocephaly, and hydrocephalus.	Determines where a child's BMI falls on CDC growth charts for ages 2–20. Use it at well-child visits or when a pediatrician asks you to track healthy weight trends over time.