Height Calculator

Predict a child's adult height based on current height, weight, and parental heights using the Khamis-Roche method. Also converts height between feet/inches and centimeters.

Calculator

Child Height

Mother's Height

Father's Height

Results

Enter values and click Calculate

Results will appear here

Predicting How Tall Your Child Will Be

To estimate future height for a child aged 4 to 17.5, this height calculator uses the Khamis-Roche method, combining the child's current height and weight with the average of both parents' heights. The result includes a typical expected range of about ±5 cm, which is why it is best described as a height predictor that gives a realistic estimate rather than an exact guarantee.

For children outside that age range, the calculator falls back to the parents-only mid-parental height formula. No height predictor is 100 percent accurate, because adult height depends on genetics, nutrition, and health, so treat the answer as a well-informed height estimator for how tall will I be or how tall my child is likely to become.

How to Use

For children aged 4 to 17.5, the calculator uses the Khamis-Roche method, a well-validated regression technique that combines the child's current height and weight with the average (mid-parental) height of both parents. The result includes a typical expected range of about ±5 cm.

How It Works

Predict a child's adult height based on current height, weight, and parental heights using the Khamis-Roche method. Also converts height between feet/inches and centimeters.

Formula / Calculation Method

This calculator uses standard mathematical formulas for accurate results.

Example

Try the calculator above with your own values to see personalized results.

Frequently Asked Questions

How does the height prediction work?

For children aged 4 to 17.5, the calculator uses the Khamis-Roche method, a well-validated regression technique that combines the child's current height and weight with the average (mid-parental) height of both parents. The result includes a typical expected range of about ±5 cm.

What is the parents-only prediction?

The parents-only prediction uses the Tanner mid-parental height formula, which averages both parents' heights and adjusts by 6.5 cm for the child's sex. Most children finish within about ±8.5 cm of this estimate.

Why is the prediction less reliable for very young or older children?

The Khamis-Roche method is validated for children aged 4 to 17.5 years. For children outside that range the calculator falls back to the parents-only estimate, which is a useful but less precise guide.

What size should I be based on my height and weight?

Body size based on height and weight is most often assessed with Body Mass Index (BMI), which categorizes weight relative to height. Use our BMI calculator for that breakdown. For predicting how tall a child may grow, use this height calculator.

What height percentile is my child in?

Height percentiles compare a child's height with others of the same age and sex using growth charts such as the CDC or WHO charts, which pediatricians use to track healthy growth. This height calculator predicts a child's likely adult height; for a precise percentile, compare your child's height against an official growth chart for their age and sex.

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