How to Use the Baby Age Calculator
Select your baby's birth date and instantly see the total days elapsed, current age in weeks and months, and developmental stage. This tool is useful for tracking vaccination schedules, starting solids timing, and pediatric checkup milestones.
Growth Stage Reference
- Newborn โ 0 to 28 days (0โ4 weeks)
- Infant โ 1 to 11 months
- Toddler โ 12 to 35 months
- Young Child โ 36 months (3 years) and older
How Weeks and Months Are Calculated
Weeks = total days รท 7 (integer part). Months = total days รท 30.44 (average month length). Because months vary in length, results may differ by 1โ2 days from calendar-based calculations used by pediatricians.
Frequently Asked Questions
Use the corrected age. Enter the original due date instead of the actual birth date, or add the weeks premature (ร7 days) to the birth date before entering.
This calculator uses 30.44 as the average month length. Doctors often use calendar-based months, so results may differ slightly.
Yes, enter each baby's birth date separately. For premature twins, apply the corrected age method to both.