Child Growth Lab

Pediatric growth calculators based on CDC and WHO growth standards.

Child Growth Lab

Growth Velocity Calculator

Calculate how quickly a child grows between two measurements.

Pediatric growth calculators based on CDC and WHO growth standards.

Measurement 1
Measurement 2

Enter both height measurements, both weight measurements, or both pairs.

Plain-language interpretation

A positive result means the measurement increased; a negative result means it decreased. Measurement technique, timing, and normal short-term variation can affect the calculated rate. This calculator provides a measurement of growth rate and is not a medical diagnosis.

Methodology

Height velocity = (second height − first height) ÷ elapsed years. Weight velocity = (second weight − first weight) ÷ elapsed months. Calculations use the exact number of calendar days between measurements, with 365.2425 days per year and 12 months per year. Metric conversion uses exact standard conversion factors.

Applicable age range

The arithmetic calculation is not tied to a growth-chart age range. Use accurately dated measurements taken during childhood. No CDC or WHO percentile standard, age-specific threshold, or diagnostic classification is applied.

Worked example

If height changes from 120 cm to 126 cm over approximately one year, height velocity is about 6 cm/year. If weight changes from 24 kg to 25.2 kg over six months, weight velocity is about 0.2 kg/month.

Limitations

  • Results depend on accurate, comparable measurements.
  • Short intervals can magnify ordinary measurement error.
  • The calculator does not assess percentiles, growth patterns, or clinical significance.
  • It does not diagnose growth problems or recommend treatment.

References

FAQ

What is growth velocity?
Growth velocity describes how quickly height or weight changes between two dated measurements.
How is growth velocity calculated?
Height change is divided by elapsed years to report centimeters per year. Weight change is divided by elapsed months to report kilograms per month.
Does growth velocity diagnose growth problems?
No. This calculator reports the mathematical rate of change only. It does not apply diagnostic thresholds or determine whether growth is typical.

Content maintenance date: 2026-07-16. Editorial and methodology review: see Editorial and methodology review.