HomeCalculatorsBaby Growth Chart
📊 Growth Calculator

Baby Growth Chart Calculator

Calculate your baby height-for-age and weight-for-age percentiles using WHO Child Growth Standards (0 to 36 months). Includes genetic adult height target from parental heights.

Enter Details to Calculate

Fill in the fields and press Calculate. Grandparent inputs are optional but improve accuracy.

Baby details
Baby's current measurements
Parent heights  used for genetic height target
Your Result
Awaiting input

TraitGen Genetics Calculator Result

Generated at traitgen.com. Free genetics education. Not medical advice.

🧬
No result yet

Fill in the form and press Calculate to see your result here.

⚠️ Educational only. Probability estimates based on genetic models, not medical advice.

📊 Did you know?

The WHO Child Growth Standards were developed using data from children in six countries: Brazil, Ghana, India, Norway, Oman, and the United States. The study deliberately selected children raised in optimal conditions, including exclusive breastfeeding and non-smoking households, to establish what healthy growth looks like rather than what is merely average.

Understanding baby growth charts

Growth charts plot a baby's measurements against reference data collected from large populations of healthy children. The WHO Child Growth Standards (0 to 5 years) are the most widely used global reference, based on data from children raised in optimal health conditions across six countries including India.

What percentiles mean

A percentile ranking indicates what proportion of children of the same age and sex your baby's measurement exceeds. A child at the 50th percentile is exactly at the median: half of healthy children that age measure more and half measure less. Being at the 10th or 90th percentile is normal. Concern generally arises only outside the 3rd to 97th percentile range, or when a child crosses multiple percentile lines rapidly.

Height-for-age vs weight-for-age

Height-for-age reflects long-term nutritional adequacy and overall growth trajectory. Weight-for-age reflects current nutritional status. Weight-for-height (also called BMI-for-age in older children) is the most sensitive indicator of acute malnutrition or overweight. Paediatricians assess all three together rather than relying on any single measurement in isolation.

Genetic target height

The mid-parental height formula provides an estimate of a child's genetic height ceiling, calculated as (mother's height + father's height + 13 cm for boys, or minus 13 cm for girls) divided by 2. A child growing consistently below their genetic target percentile despite adequate nutrition warrants paediatric review, as it may indicate a growth hormone or thyroid issue.

Growth velocity matters more than single measurements

A single measurement at one point in time provides limited information. Growth velocity (the rate of change between measurements over time) is far more clinically meaningful. A child at the 10th percentile who is growing at a normal velocity is healthy. A child who was at the 75th percentile and has dropped to the 25th over six months warrants investigation regardless of their absolute measurement.

Frequently Asked Questions

What is a normal growth percentile for a baby?

Any percentile between the 3rd and 97th is considered within the normal range for healthy children. There is no single ideal percentile. A baby consistently at the 10th percentile is growing normally if they follow that curve consistently. The key indicator paediatricians look for is whether a baby is following their own growth curve over time, not their absolute percentile position.

Should I be worried if my baby is below the 50th percentile?

No. The 50th percentile means exactly half of all healthy babies measure less and half measure more. Being below the 50th percentile simply means your baby is smaller than average for their age, which is entirely normal for roughly half of all children. Concern arises when a baby falls below the 3rd percentile, crosses two or more major percentile lines downward, or shows markedly slowed growth velocity compared to previous measurements.

How often should I measure my baby's growth?

The WHO and most paediatric guidelines recommend measuring length or height, weight, and head circumference at every well-child visit. In India, the recommended schedule typically includes visits at birth, 6 weeks, 10 weeks, 14 weeks, 6 months, 9 months, 12 months, 15 months, 18 months, and annually from age 2 onward. More frequent monitoring is recommended for preterm babies or those with growth concerns.

Does a baby's current size predict their adult size?

Not reliably in the first year. Many babies experience catch-up or catch-down growth in the first 18 to 24 months as they shift toward their genetically determined growth channel, which is predicted by parental heights. After age 2, growth percentile tends to stabilise and correlates more strongly with adult height. Preterm babies in particular often follow adjusted growth curves for the first two years.