Baby & child age calculator
Weeks, then months,
then years.
The early years are counted differently — in weeks at first, then months, long before anyone says “years old.” Enter your baby or child’s date of birth and EPOCH shows the age in weeks, months and days, the way milestone and feeding charts do.
0years0months0days
- in months
- 0
- in weeks
- 0
- in days
- 0
- in hours
- 0
- in minutes
- 0
- in seconds
- 0
Reading the early years
Look to the headline for the years-months-days figure a form usually wants, and to the “in weeks” box for the number that matters most in the first few months. EPOCH counts real calendar months, so a child born on the 31st is handled correctly even in shorter months.
This is chronological age from the birth date. For premature babies, paediatricians often use a corrected age instead — a clinical adjustment this tool does not make. For the assessment definition of age, see the chronological age calculator.
Frequently asked questions
How do I calculate my baby’s age in weeks?
Enter your baby’s date of birth. EPOCH shows the age in completed weeks (in the “in weeks” box) alongside months and days — the units used on milestone and feeding charts.
When do you switch from weeks to months for a baby’s age?
Convention varies, but many parents and paediatricians count in weeks for roughly the first 8–12 weeks, then switch to months. EPOCH shows both at once so you can use whichever the situation calls for.
How many months old is my child?
The “in months” box gives the total completed months, while the headline shows years, months and days together — handy for forms that ask for a child’s age in years and months.
Is corrected age for premature babies the same thing?
No. Corrected (adjusted) age subtracts the weeks a baby was born early from their chronological age. This tool gives chronological age from the birth date; ask your paediatrician about corrected age for development tracking.