About this tool
A baby age in months calculator tells you how many full months and extra days have passed since the birth date, for forms, photo captions and keeping track of milestones.
Enter the birth date and the tool counts calendar months: a baby born on March 10 is 2 months old on May 10, and if the month has no matching day, the last day of the month counts.
For example, a baby born 75 days ago is 2 months and about 14 days old, in the 76th day of life if the birth day is counted as day 1. How do I count the 100th day?
The tool counts the birth day as day 1, so day 100 falls 99 days after birth, and it shows how many days are left. How is this different from the years-based age?
Months are counted from the birth date, not from the calendar year, so for years use the Korean age calculator, and for a plain count between two dates use the date calculator.
The D-day calculator can also count toward a celebration date. This tool only counts calendar time and does not use corrected age, so follow your own records for that. Nothing you enter leaves your browser.
How to use
- Pick the baby's birth date.
- Read the full months and extra days, the weeks and the day count since birth.
- Check how many days are left until day 100 and the first birthday.