Baby Age Calculator
Baby age, week by week

42 Weeks Old — How Many Months?

A 42-week-old baby is 294 days old — about 9 months and 20 days.

This week

Standing alone for a second or two - wobbly, proud, unforgettable.

The math

42 weeks = 294 days ≈ 9 months + 20 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 42

At 42 weeks your baby is near the 10 Months mark. Around this age, many babies:

  • Stands alone for a few seconds
  • Understands simple asks and follows along
  • Waves bye-bye and claps hands

Milestones near this week