Baby Age Calculator
Track your baby's age with our free baby age calculator. Enter your baby's birth date to instantly see their age in weeks, months, and days. Perfect for tracking developmental milestones, scheduling vaccinations, and celebrating those precious early moments.
Enter your baby's birth date to see their age in weeks, months, and developmental milestones
How dates are counted
Age is counted from the birth date to today’s date in your own local calendar (no time of birth). Weeks are complete 7-day periods plus leftover days; months are completed calendar months, where a short month’s last day counts (born Jan 31 → 1 month on Feb 28/29). No averages like 30 or 365 days are used. Future birth dates are rejected; Reset clears the date.
Milestone timings are general guides, not medical advice. For babies born before 37 weeks, use the Adjusted Age Calculator for development.
Sources: US Naval Observatory: Leap years; AAP HealthyChildren: Corrected age for preemies
How to Use This Calculator
- Enter your baby's date of birth
- Click "Calculate Age"
- View age in weeks, months, and total days
- See upcoming milestones and development stages
Frequently Asked Questions
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