Weight, height and BMI percentile calculator for children, with optional birth data, preterm adjustment and growth trend visualization.
Based on World Health Organization (WHO) growth standards
Medical reference formulas such as Schofield and Fenton
Future height prediction using the Khamis-Roche model
The calculators on the KidGil website are intended as a general guide only and are not a substitute for professional medical or nutritional advice. Every child develops differently. If you have concerns about your child’s growth or health, consult a pediatrician or a registered dietitian.
Future height prediction is a statistical estimate rather than an exact forecast, but it may still help parents understand the child’s overall growth direction.
To get a more accurate result, choose the level that best reflects most days of the week.
Most of the day is spent sitting — studying, screen time, or quiet indoor activities. Very little physical movement beyond basic daily routines.
Daily walking to school, casual outdoor play, or light movement during the day without structured exercise.
Regular outdoor play, sports classes such as football or dance, or exercise around 3–5 times per week.
Children who train regularly or participate in intensive sports activities almost every day.
Tip: If you are unsure between two levels, choose the lower one. You can always adjust calorie needs later according to appetite and actual growth patterns.
At the top of the dashboard you will see all the data you entered: sex, age, weight, height, birth status (preterm or full-term), and parental height used for future height prediction.
This step allows you to verify that the information is correct before interpreting the percentiles and results.
Next, the dashboard displays between 3 and 6 scales depending on the available data and selections:
Body Mass Index adjusted for age and sex. The result is classified into categories such as underweight, healthy weight, overweight, and obesity risk.
Shows where the child falls compared to other children of the same age and sex.
Displays the child’s height relative to standard growth curves.
Weight is displayed on Fenton or WHO growth curves with corrected age (only when the child was born preterm).
An estimate of recommended daily calorie intake based on age, sex, body data, and activity level.
A statistical estimate based on the Khamis-Roche model, combining parental height with the child’s current growth measurements.
Below the scales you will find charts showing the child’s position on weight and height percentile curves, and sometimes a dedicated preterm chart.
These graphs help visualize whether growth is consistent over time or if there is a change that may require attention.
There are several situations where an online calculator may not be enough, and a personalized consultation is recommended.
When a child’s weight or height falls in a very low or very high percentile.
When there is a sudden change in percentile (a rapid increase or decrease).
For children with medical conditions, including prematurity, congenital heart conditions, or chronic illnesses.
When there are concerns about picky eating, poor appetite, or rapid weight gain.
The dashboard is designed for children from birth through adolescence, including growth monitoring for preterm babies. It is based on WHO growth charts for ages 0–19, with high-resolution age calculation from birth, and also includes up to 50 weeks of Fenton data for preterm infants.
In many cases, percentiles in the range of 10 to 90 are considered within the expected range. However, it is always important to look at the trend over time: is the child staying in a similar percentile range, or is there a sharp rise or drop?
Not necessarily. Some children are naturally smaller, while others are taller or leaner by nature. If the percentile is very low, or if there is a sudden change in percentile, it is a good idea to consult a pediatrician and a pediatric dietitian to better understand the reason.
Growth in preterm babies cannot be interpreted in the same way as growth in full-term infants. The dashboard takes into account gestational age at birth, birth weight, and corrected age, and combines Fenton charts for preterm babies with WHO growth charts as the child grows and approaches corrected age.
Our prediction model combines two recognized medical tools to provide the most accurate estimate possible. First, the system calculates the genetic target height using the Tanner method, based on the height of both parents.
For children aged 4 and older, the system also applies the Khamis-Roche formula, which is considered especially useful because it combines the child’s current height and weight together with parental height.
It is important to remember that this is a statistical estimate, and the result is presented as an approximate range rather than an exact prediction.
Growth tracking, charts for babies and preterm infants, BMI, readiness for solid foods, baby stool color checks, and more — all in one place to help you quickly understand your child’s development with confidence.
