Baby age, week by week
13 Weeks Old — How Many Months?
A 13-week-old baby is 91 days old — about 2 months and 30 days.
This week
Grabbing begins - hair, necklaces, everything. Drooling ramps up too.
The math
13 weeks = 91 days ≈ 2 months + 30 days
A month is longer than 4 weeks — on average 30.44 days — so you can't just divide by 4. The exact answer shifts a little with the calendar, so for the day-perfect number, use the calculator with your baby's real birthday.
Get the exact age →What babies do around week 13
At 13 weeks your baby is near the 3 Months mark. Around this age, many babies:
- Lifts their head and chest when lying on their tummy
- Watches faces closely and follows moving things
- Smiles at people all on their own