An infant is generally considered a baby from birth up to about 1 year of age, with some contexts extending the upper limit to around 2 years.

Quick Scoop: What age is an infant?

  • Most medical and parenting sources use birth to 12 months as the standard infant age range.
  • Within that, a “newborn” is often used for babies up to about 1–3 months (or sometimes just the first 28 days).
  • After about 12 months, children are usually called “toddlers,” typically from 1 to 3 years.
  • Some clinical or research guidelines may stretch “infant” up to 24 months, but this is less common in everyday use.

Simple breakdown

  • Newborn: birth to roughly 1–3 months.
  • Infant (most common use): birth to 12 months.
  • Toddler: about 1 to 3 years.

So if you’re asking “what age is an infant?” for general use (parenting, everyday conversation, most medical advice pages), the safest answer is: from birth until the first birthday.

Information gathered from public forums or data available on the internet and portrayed here.