Motor Skills

Sitting

Child sitting up playing with the Tummy Time Wobbler by Lovevery
Topic

Motor Skills

May start as early as

4 to 6 months

May peak around

5 to 9 months


Skills that come first

Head Control, Tummy Time, Rolling

Related skills

Crawling

Learning to sit independently gives your baby a whole new perspective on their world, which up until now they’ve mostly viewed from your arms ❤️ Once your baby learns to sit up on their own, they can use their hands to explore playthings, foods, and objects within reach. Learn what pediatric physical therapists and child development experts recommend—and discourage—as your child explores this skill.  


In this article:


When do babies sit up? 

Your baby may begin trying to sit up, leaning on their hands for support, around 4 to 6 months of age. By around 5 to 9 months, your baby may be able to sit up on their own briefly before needing help. 

Like all developmental milestones, sitting is a progressive skill. As your baby gets stronger and learns to balance their weight, they’ll be able to sit for longer. Most babies can sit independently for several minutes by about 6 to 9 months of age and get into a sitting position by themselves by 9 months. 

Child development expert Rachel Coley explains when babies learn to sit up, and the skills your baby develops on the way to sitting:

In video: Slide & Seek Ball Run and Organic Cotton Rainbow Ball

Sitting is a skill that babies work on across a wide range of ages. Keep in mind that developmental milestones are based on averages, and every baby develops on their own unique timeline.

How do I know when my baby is ready to sit up?

Babies learn to sit up in stages as their muscles strengthen and their balance improves. In order to sit up, your baby first needs to develop head and neck control, as well as core and upper body strength—so give them lots of time playing on the floor to build a solid foundation for sitting. Tummy time, side-lying play, and playing on their back all help your baby build the motor skills and muscle strength they need for sitting up.

One prerequisite skill for sitting is head control. To sit without support, your baby needs to be able to maintain their head upright without bobbing, and easily turn their head in both directions. 

More signs that suggest your baby is almost ready for independent sitting include:

  • Bearing their weight on straight arms during tummy time, with their hands on the floor
  • Grabbing their feet while lying on their back
  • Rolling in both directions

Tripod sitting

A clear sign that your baby is getting ready to sit up independently is when they begin sitting in a tripod position, usually around 4 to 6 months of age. In a tripod sitting position—also called “prop sitting”—your baby sits upright while leaning forward on their hands for support. Pushing through extended arms is a skill your baby can practice during tummy time that will help them support their weight while tripod sitting.

In a tripod sit or prop sit, your baby supports their weight by pushing up on their arms from the floor—a skill they can practice during tummy time. In video: Spinning Rainbow

When your baby first tries tripod sitting, they may seem a little wobbly—and that’s okay. Wobbling a bit is an important part of developing balance while seated. Tripod sitting helps your baby practice their balance with support from their hands.

You can offer light support by putting your hands on your baby’s torso to help them remain stable and prevent them from toppling over—their protective reflex to prevent falling hasn’t quite developed yet. Hold a favorite plaything in front of your baby at chest or eye level while they’re seated to determine the best way to offer support: Do they need your hands at their upper rib cage, their lower rib cage, or down at their hips to keep from falling over? 

Progressing from tripod sitting 

Once your baby can maintain the tripod sitting position for at least 30 seconds, you may begin to see these signs of progression in their sitting skills:

  • Your baby’s hands may slowly move closer to their body, changing their base of support as they get stronger.
  • Your baby will briefly lift their hand to reach for a toy in front of them.
  • Your little one may wiggle their body and dance while sitting 🙂

As they practice the skill of reaching while sitting, offer toys that can be grasped with one hand, like the Spinning Rainbow or Magic Tissue Box (both from The Senser Play Kit). You can also wrap a nursing pillow around their front, which encourages a more upright position with arm support.

Reaching while sitting helps your baby develop balance and core muscle strength. In video: Magic Tissue Box

How can I help my baby sit up?

You can help your baby prepare for sitting with activities that strengthen their muscles, build head and neck control, and let them practice movement and balance. Floor time, tummy time, supported sitting practice, and limited time spent in baby seats can all help your baby learn to sit up independently.

Floor time

Give your baby plenty of time to play on the floor in a variety of positions. Floor time allows your baby to explore and learn how their body moves. This freedom of movement can help your baby develop:

  • Body awareness: An understanding of the position and movement of their body, also known as proprioception
  • Spatial awareness: Knowledge about how their body interacts with the world around them, and where they are in relation to objects and other people
  • Balance: Control of body stability using core strength and trial-and-error experience.
  • Cause and effect: Discovering the effects of their body’s movement through every kick and reach.

Try to give your baby supervised floor time throughout the day with an exploration toy like The Play Gym, the Tummy Time Wobbler, or the Rolling Bell. Brief floor time sessions several times a day can lay the foundation for many skills to come.

Tummy time

Tummy time is helpful for so many aspects of your baby’s motor development, including sitting up. Daily sessions of tummy time can help strengthen your baby’s neck, shoulder and arm muscles, all of which they eventually use to sit upright on their own. Research shows that babies who get routine tummy time sessions may develop certain motor skills earlier, including rolling, crawling, and sitting up. 

Surrounding your baby with a few fun playthings during tummy time is a great way to inspire pivoting as they play on their tummy, which can build core strength and body coordination. Place your baby on a mat on their tummy, then arrange the Spinning Rainbow, Tummy Time Wobbler, and Organic Cotton Rainbow Ball (all from The Senser Play Kit) in a semi-circle around them. Let your baby move freely from one plaything to the next. 

Supported sitting

As your baby’s core muscles get stronger, giving them opportunities to sit with support will help build their strength, body control, balance, and confidence—all of which will eventually help them to sit up independently.  

Supporting your baby while they practice sitting can take many different forms—here are a few examples of what supported sitting can look like: 

  • Sitting behind your baby with a leg on each side as you explore a book together
  • Protecting them from a hard tumble by surrounding them with a nursing pillow or throw cushions
  • Placing them in the corner of a couch where the back meets an armrest
  • Putting them in a laundry basket surrounded by pillows.
  • Putting a couch cushion in front of them so that they can prop-sit with their arms on a higher surface
Give your new sitter lots of practice with support from you. In video: Rolling Bell

In all these scenarios, it’s good to let your baby wobble—a little. Research shows that wobbling offers important feedback for a baby learning to sit independently. Just be aware that your baby hasn’t mastered protective reactions yet, so they won’t be able to catch themselves when they tumble during sitting practice. This is why you’ll want to stay close, and create a safe landing area away from hard surfaces and onto something soft. Remember never to leave your baby unsupervised with blankets or pillows.

Limited time in baby seats

While baby seats can be convenient, they don’t help babies learn how to sit up. In fact, some seats put your baby in an unnatural sitting position, causing them to round their back, and making it harder for them to engage their core muscles.

If used too often, baby seats can actually get in the way of your baby learning to sit up. Baby seats also don’t allow for the natural movements that occur during sitting, like transitioning to a side-sitting position to grab a toy outside of their reach. This is why pediatric physical therapists recommend minimizing the use of baby sitting devices that don’t give babies opportunities to learn balance through wobbling.

It’s best that your baby spend as much time as possible unrestricted by confining gear like baby seats. If your baby does use a baby seat or activity seat, try to limit seat time to 20 minutes or less per session.

There are many baby seat products on the market, but unfortunately, their design is not always supported by research or best practices for your baby’s development and physical needs. Baby seats are considered a type of container that can be used to free up your hands while your baby is safely in one spot, but aren’t essential for your baby’s sitting development. If you decide to use a baby seat in your home, consider the following:

  • Upright posture: Your baby’s back should be upright and not rounded. 
  • Hip positioning: Your baby’s hips should have plenty of room to spread and fall to the side in a “ring” position. Some seats restrict movement and keep a baby’s legs in a narrow position, which is not optimal for healthy hip development. 
  • Body positioning: Your baby should sit with their weight distributed equally between their hips, without leaning to either side.

Sitting stages and progression by age

You can help your baby prepare for sitting with activities that strengthen their muscles, build head and neck control, and let them practice movement and balance.

Sitting with support (4 to 5 months)

At first, your baby will need plenty of support from you while sitting. Place them in your lap or on the floor in front of you with your hands holding their ribcage.

Child playing with the Treasure Basket and Magic Tissues from Lovevery
Support a brand-new sitter with your hands around their ribcage. In photo: Treasure Basket and Magic Tissues

As your baby becomes more stable, you can gradually offer less support. Place your hands slightly lower on their trunk and hold them a little less tightly. Offer them a variety of toys to grasp, mouth, and play with in this supported seated position.

Prop sitting or tripod sitting (4 to 6 months)

When your baby uses their hands to balance, they’re “prop sitting” or tripod sitting. Offer them toys to look at rather than grasp at first, since they need both of their hands for support in this position. Hold the toy in front of their face, moving it from side to side so your baby looks up and around while sitting. Place a baby-safe mirror like the Framed Mirror in front of your baby to encourage them to lift their head in this position.

If you notice your baby folding forward in this sitting position, wrap a nursing pillow around their front, or put a couch cushion in front of them to encourage a more upright position while pushing through their arms. 

Once they start to lift one hand while seated, using their other hand to stay balanced, give them simple grasping toys.  

Wobbly sitting (5 to 7 months)

When your baby first begins to sit up on their own, they may be wobbly—and that’s okay. Wobbling is the primary way your baby figures out how to balance without using their hands. 

Wobbling is how babies learn to balance while sitting, an important part of this developing skill.

New and wobbly sitters typically have a brief period of keeping their arms in a “high guard” or field-goal position while they work on maintaining their balance in this new way of sitting.. You’ll need to spot them during this stage, as they haven’t yet developed protective instincts to counter a fall. For safer wobbling, you can sit behind them with your legs in a V, using your arms and legs as a boundary.

Try the following to support this stage, always remaining at arm’s reach:

  • Wrap a nursing pillow behind your baby’s hips and back to offer low, gentle support—and a soft spot to tumble when they tip over ❤️
  • Put them in an empty laundry basket with throw pillows on all sides. 
  • Offer playthings to your baby at their chest level to keep their center of gravity low, like the Spinning Rainbow or Magic Tissue Box from The Senser Play Kit

Remember never to leave your baby unsupervised with pillows or blankets.

Independent sitting (6 to 8 months)

Your baby is considered an independent sitter once they can sit unsupported for at least 30 seconds. Once they’re stable in an unsupported sitting position, you can offer them new way to build their skills. Place toys around your baby to encourage them to turn their head, twist their torso, and reach in different directions while maintaining their balance. Offer small and large toys to practice transferring objects between hands and lifting with both hands—both will challenge your baby’s sitting balance. 

Supervising your baby closely, try suspending toys above them—from The Play Gym or tucked between couch cushions—so they need to reach up and grab them. You can also place toys on the floor at a diagonal, just barely out of reach. This encourages your baby to reach with one arm and then return to an upright position, a great core strengthening activity.

Once your baby becomes confident sitting independently with their legs in a “ring” or circular position, you may see them exploring a new movement, called side sitting. Side sitting is when your baby has one knee bent in front and the other one knee bent behind. This position is important for transitions, because it makes it easier for your baby to get out of sitting onto their tummy to prepare for crawling.

Child playing in The Play Gym by Lovevery
Place interesting toys within reach of your newly independent sitter to encourage their skills. In photo: The Play Gym

Functional sitting (7 to 11 months)

Functional sitting means your baby can transition on their own from their belly or from crawling into a sitting position, and back down again. Most babies can get into a sitting position from the floor by themselves by 9 months of age. Offer toys, books, and other playthings spread out around the room to encourage their exploration and to keep practicing those transitions.

How can I help my baby get in and out of a sitting position by themselves?

Getting out of a sitting position

Babies get themselves out of a sitting position and onto the floor by supporting their upper body with their hands and slowly walking their hands forward until they’re on their tummy. This transition takes upper body and core strength to control their slow descent to the floor. 

To help your baby practice this movement, place toys just out of their reach that encourage them to support themselves with one arm and reach with the other. Your baby might also move their legs from a ring position to a side-sit position, since this change in leg position makes it easier to balance while getting a better reach. 

While your baby is learning how to control their body’s movement down to the floor, you may want to place a folded blanket in front of them or use a padded mat to cushion any falls.

Getting into a sitting position

For your baby, getting into a sitting position is more challenging than getting out of sitting, partly because the movement itself is more complex, and partly because they’re moving against the pull of gravity. 

There are two common ways babies make this transition: from tummy to sit, and from back to sit. 

Tummy to sit: Babies get into sitting from their tummy by rotating their hips, lifting one hip off the floor, and walking their arms back to bring their body into sitting. If you see your baby rotating and lifting their hip, help them along by guiding their lifted hip to the floor and support under their opposite armpit as needed.

Back to sit: Babies get into sitting from their back by rolling to their side and pushing their body up with their hands, bringing their top hip down to the floor. It may feel instinctive to hold your baby’s hands to help them pull up into sitting as you did when working on their head control; instead, you will want to help them push through their arms rather than pulling, which teaches them how to do this on their own. To practice this movement, roll your baby to his side, lift under their lower armpit and gently pull their top hip down to the floor. Once your baby has sufficient head control, you can practice this movement each time you pick your baby up from the floor or after every diaper change.

Your baby may find one movement pattern that they’re strongest in and stick to it, while slowly developing the other. It’s not expected that your baby would learn both of these patterns at the same time, so there’s no need to worry if one pattern is stronger than the other. Most babies learn how to get into a sitting position from the floor by 9 months of age. 

Troubleshooting with sitting: folding forward or flinging backward

Learning to sit in an upright position requires your baby to balance the effort of their core and back muscles. Some babies fold forward while sitting, while some fling their body backward, both of which limit their ability to play and learn while sitting. Either way, you’ll want to stay close to them for support.

If you notice your baby folding forward while sitting, wrap a nursing pillow around their front or place a removed couch cushion in front of them to push up from. Place their favorite toys at or above their chest height to encourage a more upright posture. 

If you notice your baby flinging backward while sitting, they are likely overpowering their sitting with their back muscles. You’ll want to include activities that engage a downward gaze and forward reaching, so place their favorite toys below their chest height—ideally toys that can’t easily be picked up, such as the Spinning Rainbow or Magic Tissue Box (from The Senser Play Kit). Set up pillows behind them, but not touching them, and support them by their legs instead of supporting their back.

RELATED: Supporting your new little sitter

What is W-sitting?

Once your baby learns to sit unsupported, you may sometimes see them use a W-sitting position. This is when your child sits with their bottom on the floor, their knees forward, and their feet pointing back and legs to the sides. Looking at your child from above, their legs form a W shape. 

It’s not uncommon for babies and toddlers to use the W-sitting position. For many children it provides a comfortable sitting position for the following reasons:

  • Stability: W-sitting gives babies a wide, stable base of support, which allows more precise fine motor control.
  • Transition: W-sitting provides a quick, easy transition from crawling that doesn’t require torso rotation, a complex motor skill.
  • Flexibility: Children can comfortably sit in this position, so it’s more available to them than it is to most adults.
W-sitting is a comfortable play position for many babies. You can help them explore different sitting positions to encourage balance and strength. In video: Bunnies in a Felt Burrow

Is W-sitting bad?

Overall, research doesn’t support the notion that W-sitting is inherently detrimental to children’s development. Some children have an increased twist in their thigh bone (called internal femoral torsion) which allows them to W-sit very easily. This twist usually disappears without intervention as children grow. Research shows that the W-sitting position does not contribute to a greater chance of hip dysplasia.

If your baby uses a W-sitting position occasionally, along with other sitting positions, it is generally not a cause for concern. Reach out to your pediatrician about consistent w-sitting if your baby:

  • Doesn’t sit well or for long in other positions, like with legs criss-crossed in front of them or legs extended straight
  • Has known orthopedic issues like hip dysplasia
  • Has been identified as having low muscle tone or gross motor delays

Developmental concerns with sitting

Babies develop at different rates for a variety of reasons, including genetics, temperament, experience with different skills, and many other factors. Research from a variety of countries around the world shows that most babies learn to sit up unassisted by 9 months of age. If your baby reaches 9 months of age and is not yet sitting up, the Centers for Disease Control and Prevention (CDC) recommends reaching out to your pediatrician.

If your baby shows other signs of muscle weakness, or prefers to use only one side of their body, this should also be discussed with your pediatrician. They can assess your baby’s developmental path and recommend a physical or occupational therapist if needed. You may also reach out to your state’s early intervention program to see if your baby is eligible for services.  

Safety considerations for sitting babies

Once your baby has mastered sitting up unassisted, greater mobility is just around the corner. To prepare for having a baby on the move in your home, think about these safety measures:

Lower your baby’s crib mattress. Now that your baby can sit upright, they may soon begin pulling up using the crib rail. Keeping the mattress low helps prevent accidental falls.

Never leave your baby sitting unsupervised on a raised surface such as a countertop or bed. Even if your baby has strong sitting skills, they can still fall easily from a high surface.

Stay close. As your baby builds sitting stability, be sure to surround them with pillows or a soft surface, and stay close in case they wobble or fall.

Keep your baby secure. If you use a high chair or baby seat, use the safety straps to secure your baby. 

Start babyproofing, if you haven’t already. Now is a good time to look around your home for potential hazards such as chemicals, loose strings from window coverings, electrical outlets, and stairs. Secure any items that are unsafe and install baby gates and outlet covers.

RELATED: Why and how to babyproof early

Posted in: 3 - 4 Months, 5 - 6 Months, 7 - 8 Months, 9 - 10 Months, Motor Skills, Gross Motor, Sitting, Balance, Head Control, Motor Skills

Meet the Experts

Learn more about the Lovevery child development experts who created this story.

Rachel Coley, MS, OT/L
Rachel Coley is a pediatric occupational therapist and child development expert, and founder of CanDo Kiddo.
Maral Amani, PT, DPT
Maral Amani is a licensed pediatric physical therapist certified in early intervention who works with children living with disabilities, delays, and neurodivergence.
Gabrielle Felman, MSEd, LCSW
Gabrielle Felman, founder of Felman Early Childhood Consulting, works with children from birth to age 7 to support social, emotional, and cognitive learning.
Giselle Tadros, PT
Dr. Giselle Tadros is the founder of In-Home Pediatric PT of NJ and Milk Matters PT. She has been helping babies and families in her community for over 20 years.
Amy Webb, PhD
Amy Webb, Associate Writer at Lovevery, is a child development scholar and researcher who holds a Doctorate in Human Development and Family Sciences.
Emily Newton, PhD
Emily Newton is a writer at Lovevery with over 20 years of experience as a researcher, professor, early childhood educator, and parent. She holds a PhD in Developmental Psychology and an MA in Child Development, with expertise in infant and toddler social, emotional, and socio-cognitive development.
Zachary Stuckleman, PhD
Zachary Stuckleman is a researcher and child development expert who holds a Doctorate in Developmental Psychology and is the Lead Content Researcher at Lovevery.

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