Child Height Predictor

Predict adult height from parent heights using the mid-parental method.

By Konstantin Iakovlev · Updated April 2026 · Source: CDC

Child's Sex

Predicted Adult Height

5′10″

176.5 cm

Low Estimate

5′6″

High Estimate

6′1″

Height Details

Predicted Height5′10″ (176.5 cm)
Likely Range5′6″ – 6′1″
Range in cm167.9 cm – 185.2 cm
Mother's Height5′4″
Father's Height5′10″

Uses the mid-parental height method (±3.4 inches). This predicts within 2 inches for about 50% of children. Genetics, nutrition, health, and other factors significantly affect final adult height. This is an estimate, not a diagnosis.

Use the Child Height Predictor above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only and does not constitute tax, financial, or legal advice. Results are estimates based on the information you provide and current rates. Always consult a qualified tax professional or financial advisor for advice specific to your situation.

How It Works

Genetics carries a large share of the responsibility for how tall a child eventually becomes, and the mid-parental method is the long-standing way of turning that inheritance into an estimate of adult height. This tool applies that method to project where your child's growth may be heading, which can be useful for setting expectations and following their development. It is not a fixed forecast, but it produces a statistically meaningful figure, something that matters all the more in 2026 as genetic research keeps moving forward.

At its core the method averages the biological mother's and father's heights, then adjusts that midpoint for the child's sex. For a boy, 2.5 inches (6.35 cm) is added to the parental average; for a girl, 2.5 inches (6.35 cm) is subtracted. That shift reflects the typical height gap between adult men and women and grounds the estimate in growth patterns seen across populations worldwide.

Several influences beyond genes shape final height, including nutrition, general health, and the conditions a child grows up in, so the output stays an estimate rather than a promise. Accuracy depends on entering the biological parents' heights and on accounting for any significant medical condition that can stunt growth; leaving those out is where projections tend to go wrong. Even with good inputs, a spread of about +/- 4 inches (10 cm) around the predicted figure is perfectly normal.

Example: Predicting Sarah's Adult Height

  1. 1 Step 1: Input Parent Heights. Let's say Sarah's biological mother is 5'4" (162.5 cm) and her biological father is 5'10" (177.8 cm).
  2. 2 Step 2: Calculate Mid-Parental Height. The average height is (162.5 cm + 177.8 cm) / 2 = 170.15 cm. Since Sarah is a girl, we subtract 6.35 cm.
  3. 3 Step 3: Determine Predicted Adult Height. Sarah's predicted adult height is 170.15 cm - 6.35 cm = 163.8 cm (approximately 5'4.5").
  4. 4 Step 4: Understand the Context. This means Sarah is most likely to be around 5'4.5" tall as an adult, with a typical range between 5'0.5" and 5'8.5". This prediction helps parents visualize her potential growth and provides a general benchmark for her development.

Source: CDC · Last updated: April 2026

Frequently Asked Questions

How accurate is the mid-parental height prediction?
The mid-parental method predicts adult height within a range of plus or minus 2 inches about 68% of the time. It is a rough estimate based on genetics and does not account for nutrition, health conditions, or other environmental factors that influence growth.
How do you predict a child height from parent heights?
For boys: add both parents heights in inches, add 5, and divide by 2. For girls: add both parents heights, subtract 5, and divide by 2. This gives the mid-parental height estimate. Most children will fall within 2 inches of this prediction.
At what age do children stop growing?
Girls typically reach their full adult height by age 14-16, about 2 years after the start of menstruation. Boys usually stop growing by age 16-18. Some boys continue to grow slowly until age 20-21. Growth plates fuse at different rates based on hormones and genetics.