Baby age calculator
Weeks for the first months, months after that: the age the way your pediatrician counts it.
Updated October 13, 2026 · sources checked October 13, 2026
In short
Enter your baby's date of birth to see their age today in weeks, and in months plus days. Health checks, vaccines and many milestones are counted from the birth date; for babies born early, your pediatrician may also use a corrected age, counted from the due date.
Weeks or months?
In the first weeks, most parents and professionals count in weeks; from two or three months, in months. The calculator gives both, so you can match it with your child's health record.
Born early
If your baby was born before 37 weeks, ask your pediatrician which age to use for milestones: they may use the age corrected for prematurity. Feeding advice, such as when to start solids, is also decided case by case for premature babies.
Useful next
Sources
- NHS — Your baby's first solid foods checked October 13, 2026
- WHO — Infant and young child feeding (fact sheet) checked October 13, 2026
Mamavela explains; it does not replace your midwife, doctor or pediatrician, who know your situation. If something worries you, call them. In an emergency, call 911 (US), 999 (UK) or 112.