Corrected Age Calculator for Preterm Babies (2025)
Calculate both chronological and corrected age for preterm infants using gestational age at birth and assessment date.
Medical Disclaimer
This calculator is for educational purposes only and should not replace professional medical advice. Always consult with your pediatrician or healthcare provider for medical decisions regarding your child's development and care.
Corrected age accounts for the time a preterm baby should have spent in the womb. It's calculated by subtracting the number of weeks born early from the chronological age.
Formula:
Example:
- Baby born at 32 weeks gestation
- 8 weeks premature (40 - 32 = 8)
- At 6 months chronological age, corrected age = 6 - 2 = 4 months
For complete methodology details, visit our methodology page.
When should corrected age be used?
Corrected age is typically used for developmental assessments, milestone tracking, and medical evaluations in preterm infants until around 2-3 years of age. It helps account for the time the baby should have spent in the womb.
How long should I correct for prematurity?
Most pediatricians recommend using corrected age for developmental milestones until 2-3 years of age. For some assessments, correction may be used until school age. Always consult your healthcare provider for guidance.
Which baseline should I use - 40 weeks or 37 weeks?
40 weeks is the standard full-term baseline used in most medical settings. Some practitioners may use 37 weeks (early term), but 40 weeks is more commonly accepted for corrected age calculations.