Rolling over
Most babies start rolling over at around 5 to 6 months. In a study that followed babies in Hong Kong, many rolled from back to tummy first, the opposite of what many books say.
How sure are we?
Fairly sure. Two studies in five countries agree, but there are only two so far. How we know this
What it’s a sign of
Your baby is getting stronger and learning to move their whole body on purpose.
Babies who sleep on their backs may roll and crawl a little later than babies who sleep on their tummies, though they walk at the same age. Some babies roll back to tummy first, others tummy to back.
We don't yet know the age by which nearly all babies roll.
A main source for the ages
Similarities and differences in child development from birth to age 3 years by sex and across four countries: a cross-sectional, observational study
Ilgi Ozturk Ertem, Vibha Krishnamurthy, Mphelekedzeni C. Mulaudzi, Yanina Sguassero, Hakan Balta, Ozlem Gulumser · 2018 · Lancet Global Health
- Children
- About 4,900 healthy children
- Where
- Argentina, India, South Africa and Turkey
- Ages
- Birth to 3½ years
- How
- Trained staff asked parents open questions about what their child could do, at health clinics
- What it found
- Found the age by which half of children reached more than 100 milestones. Most came at similar ages in all four countries, and for boys and girls. For example, half of children waved bye-bye by about 11 months and said a first word by about 9 months.
- Limits
- Only four countries and no rural areas, children from city clinics, and only healthy children (about half of those who came were left out for health reasons). It gives the age for half of children, not the full spread.
A main source for the ages
Rolling over in infants: age, ethnicity, and cultural differences
E. Anthony S. Nelson, Ly‐Mee Yu, D Wong, H Y E Wong, Larina C.L. Yim · 2004 · Developmental Medicine & Child Neurology
- Children
- About 240 babies
- Where
- Hong Kong
- Ages
- Birth to 9 months
- How
- Mothers recorded on a chart when their baby first rolled
- What it found
- Babies first rolled from back to tummy at about 5 months on average, and from tummy to back at about 5½ to 6 months, the opposite order to what many textbooks say.
- Limits
- We have only read the summary. A third of the mothers who signed up didn't return the chart.
A study that questioned earlier findings
Effects of Sleep Position on Infant Motor Development
Beth Ellen Davis, Rachel Y. Moon, Hari Cheryl Sachs, Su‐Ting T. Li · 1998 · PEDIATRICS
- Children
- About 350 babies
- Where
- The United States
- Ages
- First year
- How
- Parents kept a log of when their baby reached each milestone
- What it found
- Babies who slept on their tummies reached rolling, crawling and pulling to stand earlier than babies who slept on their backs, but they walked at the same age.
- Limits
- We have only read the summary, which doesn't give the size of the difference in months.
If you’re worried about your child, talk to your child and family health nurse or GP.
Last checked 2 November 2026