How to use
- Enter Date of birth, Gestational age at birth (weeks), Current date in Corrected Age Calculator for Preterm Babies. Use the freshest measurement you have, ideally from the same day or clinic visit.
Corrected Age Calculator for Preterm Babies
Calculate your preterm baby's corrected age to track development milestones accurately.
Parent guide
How to use this tool
Calculate your preterm baby's corrected age to track development milestones accurately.
What the result means
Calculate your preterm baby's corrected age to track development milestones accurately.
Method
Corrected age = chronological age − weeks born before 40 weeks gestation
Worked example
Important limitation
Corrected age supports developmental interpretation; it does not change vaccination timing unless local guidance says otherwise.
Primary sources
References and data notes
Safety note
Use this result for planning and discussion. Contact a qualified healthcare professional for unusual growth changes, feeding difficulty, fever, missed vaccines, developmental concerns, or urgent symptoms.
Next tools to compare
Baby Developmental Milestone CheckerCheck which developmental milestones your baby should reach at this age.Baby Vaccination ScheduleSee the recommended vaccination schedule for your baby based on country guidelines.Baby Weight Percentile CalculatorCalculate your baby's weight percentile using WHO or CDC growth charts. See if your baby is growing on track.
Frequently asked questions
Which sources and method does this tool use?
The method, version and primary sources are listed in the evidence section above.
Why might Corrected Age Calculator for Preterm Babies differ from a clinic visit?
Home measurements, rounding, age calculation, units, and reference choices can all shift the result. Use the same measurement method over time and bring concerns to your pediatrician.
What should I compare with this result?
Compare it with Baby Developmental Milestone Checker, Baby Vaccination Schedule, Baby Weight Percentile Calculator, recent trends, feeding or sleep notes, and your child's usual behavior. A steady pattern is usually more informative than one isolated value.