Tallness Calculator
Estimate a child’s likely adult height using common statistical methods and parental data. Results are estimates — consult a pediatrician for clinical guidance.
Estimates only. Not medical advice.
Try a demo:
Estimated Adult Height
Enter your details and click "Estimate" to see results.
Method Comparison
Bar chart showing estimated adult height by method with uncertainty ranges.
Growth Projection
Projected height trajectory from current age to adulthood.
Uncertainty Distribution
Probability distribution of possible adult heights.
How It Works
Mid-Parental Height (MPH)
Formula:
- Boys: (Father + Mother + 13 cm) / 2
- Girls: (Father + Mother - 13 cm) / 2
Typical range: ±8.5 cm (±3.35 in). Based on genetic potential.
Khamis-Roche Method
Uses current height, weight, age, sex, and parental heights. Validated for ages 4–17. More accurate than MPH when inputs are complete.
Note: This simplified implementation uses regression approximations.
Percentile Tracking
Maps current height to CDC growth percentiles, then projects adult height assuming percentile stability. Best for children >2 years.
Bayley-Pinneau (Bone Age)
Adjusts projection based on skeletal maturity. Requires bone age from X-ray. Clinical use only—consult a specialist.
References
- CDC Growth Charts
- Khamis, H. J., & Roche, A. F. (1994). Predicting adult stature without using skeletal age. Pediatrics.
- Bayley, N., & Pinneau, S. R. (1952). Tables for predicting adult height from skeletal age. Journal of Pediatrics.
All calculations happen in your browser. No data is sent or stored externally.
