How big is your baby's stomach: photos

Medically reviewed by Vinayak Pai, Consultant paediatrician

Written by Joanne Lewsley | 20 Mar 2024

Learning about the size of your baby's stomach can help you understand how much and how often your baby needs to feed. You may be surprised by how small their stomach actually is!

Photo credit: Thinkstock

Day one

When your baby is first born, their stomach is no bigger than a hazelnut. Because of its small size, your baby will need to feed often to keep themselves feeling full.

Photo credit: Thinkstock

Day two

By the second day, your baby's stomach will be about the size of a cherry. Your baby will be able to take in a little more milk with each feed, but they will still need to feed every 90 minutes to two hours.

Photo credit: Thinkstock

Day three

When your baby is three days old, their stomach will have grown to about the size of a walnut. It's grown a lot from the day they were born!

Photo credit: Thinkstock

Days four to seven

Towards the end of your baby's first week, their stomach will have grown to the size of an apricot. Your baby should start to put some weight back on and have around six heavy, wet nappies a day.

Photo credit: Thinkstock

Four weeks

The expansion of your baby's stomach will have slowed a little now. But by the time your baby is four weeks old, their stomach will be roughly the size of a large hen's egg.

Advertisement | page continues below

Photo credit: Karla Martin for BabyCenter

Adult

Your baby's stomach will continue to grow until they become an adult. Once they are fully grown, their stomach will be about the size of a large mango.

Find out more:

How much milk does your baby need in the first few days

How often should you breastfeed your baby

Was this article helpful?