Infant Car Seat Weight and Height Limits

Infant car seats and all car seats come with clearly indicated weight limits. Car seat manufacturers sometimes list the minimum and maximum heights. But the weight limit is always a given no matter the model you choose. In this post, you’ll learn the typical infant car seat weight and height limits as well as those of convertible car seats.

Related: Infant Car Seats vs Convertible Car Seats

Rear-Facing-Only Car Seat Weight Limits

The American Academy of Pediatrics recommends that parents ride with their kids rear-facing for as long as fit and weight/height limits allow. Rear-facing-only car seats are tested to protect newborns, infants, and toddlers from 4-35 pounds. This weight range typically coincides with a maximum height limit of 30″-32″.

Every manufacturer states each infant car seat’s weight limits, and it’s up to you as a parent to keep an eye on these numbers. Carrying a child who’s too heavy or too tall for a particular car seat model is not only unwise but also potentially dangerous.

Car seat crash-testing costs are humongous. When NHTSA approves a given car seat as good within a stated weight and height limit, you better stick to the rules…because NHTSA definitely knows.

When Buying an Infant Car Seat, Know the Height and Weight Limits

Here’s a baby car seat buying guide in case you haven’t yet learned how pick out the best car infant car seat or convertible car seat for a little one.  Before you settle on any particular car seat, be sure to learn the weight and height limits it offers.

But where do I find a car seat’s weight and heights? Normally, you can find a car seat’s specific weight and height limits on the car seat manual. If the seller for whatever reason didn’t send out the owner manual, find the particular model’s user manual online (start the search at the manufacturer’s website).

I’ve seen incredibly pricey infant car seats that most infants can’t use beyond month 6. Whispering: I stayed away from expensive low-weight-limit infant car seats and bought options with a 15-24 months of use instead. I’d advise you to do the same…because there’s still tons of other expensive baby gear to purchase.

When to Switch Baby to a Convertible Car Seat

Here’s a question that parents frequently ask: When is my baby too big for an infant car seat? There are two accurate ways to determine whether your child is too big for their infant car seat.

1. If the child has reached the weight and height limits indicated by the manufacturer, that’s a CLEAR indication they’ve outgrown the rear-facing-only car seat. For the vast majority of infant car seats, the minimum weight limit is 5 pounds.

A few options out there have an even lower minimum weight limit of 4 pounds. In terms of height limit, it’s time to buy a new convertible car seat with higher weight limits when your child grows to between 30″-32″. In some cases, the height limit may be as high as 35″ and a weight limit of up to 40 pounds.

2. Here’s the second way of knowing with certainty whether it’s time to move a child to a convertible car seat: If the distance from the top of the infant car seat to the top of the tiny passenger’s head is less than 1″, the child’s outgrown it.

A Common Reason Parents Stops Using a Bucket Seat

The 2 reasons above aren’t the only ones parents and other caregivers get kids out of a bucket seat and strap them into a convertible or all-in-one car seat. In case you’re interest to know, here’s a couple of differences between an infant car seat and a convertible car seat.

So here’s the third reason people decide to stop using a bucket seat: If and when the infant car seat (bucket car seat) proves too much of a hassle to carry, most people interpret that to mean it’s time to get a convertible car seat. This point arrives at different times for different people obviously because people aren’t built out the same way.

A 6-foot dad weighing 200+ pounds might carry an infant in a bucket until they reach the indicated height and weight limit while a petite mom may not do so past month 6.

When Do Most Kids Reach 30″-32″?

The average kid is ready to move to a convertible car seat between month 12 and 19. At this point, the child stands anywhere between 30″ and 32″. However, bigger, taller children tend to outgrow their rear-facing-only car seat way before they reach the seat’s weight and height limits way before month 19.

In most cases, parents of larger kids introduce them to a convertible car seat between the ages 9 months and 2 years. The bigger and heavier the child, the sooner they’re likely to need a bigger, taller, sturdier car seat with a higher weight limit to boot.

Can a Newborn Fit in a Convertible Car Seat?

If a convertible car seat is designed to fit newborns as well as older kids, then YES. Seats that fit newborns typically come with a removable infant insert that raises the child to meet the 5-point safety harness, creating a much better fit.

With that being said, many parents have noted that tiny tots tend to have a better fit overall in an infant car seat than they do in a convertible car seat. If you’re if there’s a convertible car seat that works really well for newborns and tiny babies, consider trying out the Cosco Scenera NEXT Convertible Car Seat.

Is There Any Safety Difference Between a Convertible and A RFO Car Seat?

According to the Wire Cutter, there’s no documented evidence that an infant car seat providers more protection to kids compared to a convertible car seat. In the age range 9 months to 24 months, there’s no safety difference between these two car seat types as long as the child meet’s the car seat’s minimum and maximum height and weight requirements.

Below are weight limits of a bunch of popular infant car seat models:

Chicco Infant Car Seat Weight Limit

The Chicco KeyFit 30 has a minimum weight limit of 4 pounds versus 5 pounds for most infant car seats. Its upper weight limit extends all the way to 30 pounds, and this numbers corresponds to a height limit of 30″. When it comes to a car seat of any kind, NEVER assume anything. Always check the specs, and be sure to stick to the indicated limits.

Uppababy Mesa Infant Car Seat Weight Limit

The Uppababy Mesa Rear-facing-only infant car seat accommodates tots from 4 to 35 pounds and a maximum height limit of 35 pounds. The stated maximum height limit is 32″ or 2″ taller than the Chicco KeyFit 30. Compared to the Chicco infant car seats, Uppababy Mesa infant car seats have a higher weight limit and a slightly higher height.

Graco Infant Car Seat Weight Limit

Graco infant car seats are tested for carrying babies and infants rear-facing only from 4 pounds up to 35 pounds while the max height limit tops out at 32″. As you can see, Uppababy and Graco infant car seats have the same weight and height limits compared to Chicco infant car seats.

But at the end of the day, it’s not a night-and-day limit difference, and no infant car seat ever becomes a forever car seat unless it’s a convertible car seat that accommodates newborns while offering booster mode seating for older kids down the road.

Convertible Car Seat

Unlike an infant car seat that ONLY allows for rear-facing seating, a convertible car seat makes for rear-facing seating and is then reinstalled for forward-facing seating when the rear-facing limits are reached.

Some convertible car seats allow kids to travel forward-facing up to around 65 pounds at which point they become a booster car seat. The child uses the booster seat until age 8-12, and this is when they become big enough to fit in the regular adult seatbelt.

As mentioned above and in many other places on this kid-focused website, a convertible car seat with a booster seating mode is essentially a forever car seat. It’s the option you need if the idea of spending your hard-earned money on 1-3 car seats doesn’t exactly thrill you and your credit card.

How Long Rear-facing Seating in a Convertible Car Seat?

As long as the height and weight limits listed by the car seat manufacturer allow. According to the NHTSA and AAP, it’s wise to carry children rear-facing for the longest duration possible.

Because research reveals that kids carried rear sitting (9-24 months) tend to get better protection in crashes compared to when the same age range travels forward-facing. I believe that’s part of why car seat makers warn consumers not to install forward-facing a seat that’s by design rear-facing-only.

According to the British Medical Journal (2009), carrying children rear-facing up to age 4 provides greater safety. This means kids ride seated in this position until they reach 40 pounds.

This is what happens in Sweden. And a look at accident stats in Europe shows that this country has one of the lowest figures as far as fatality rate during car accidents.

If you want extended rear-facing seating, chances are it won’t happen with an infant-specific car seat. You’ll likely find luck with a convertible car seat.

The good news is that there’s tons of such options that offer a weight limit of 40-45 pounds rear-facing. Sure, these are heavy and bulky seats. But some of these seats revolve, making it easy to buckle children in and get them out. And here’s a list of the best convertible revolving car seats in case you’re interested.


You know it’s time to forward-face when your child’s head’s top is less than 1″ from the top of the seat when the headrest is at its tallest. You also know it’s time to stop get a convertible car seat when the bucket seat’s weight and height limits are reached.

And for many parents, forward-facing begins when they can no longer comfortably the kid in the bucket seat when outside of the car. When any of these indicators show up, be sure to get a good convertible car seat, with or without a booster seat.

Author: Esther Moni

I'm Esther Moni, a proud stay-at-home mom and a psychology graduate of the United States International University (USIU) . I hate it when anyone calls me a housewife, because what does housewife even mean? Being a mother of two babies and a pup, Bailey, as well as being Ricky's wife tires me to no end, but I still manage a smile at the end of it all. And when my boys aren't done doing mischief, I juggle writing a post on parenting or baby gear performance for this blog and running my little counselling office based out in Nairobi. <a href="">Visit my Facebook profile here</a>, and this is my <a href="">LinkedIn profile</a>, and here's my <a href="">nascent youtube channel.

Esther Moni

I'm Esther Moni, a proud stay-at-home mom and a psychology graduate of the United States International University (USIU) . I hate it when anyone calls me a housewife, because what does housewife even mean? Being a mother of two babies and a pup, Bailey, as well as being a wife tires me to no end, but I still manage a smile at the end of it all. And when my boys aren't done doing mischief, I juggle writing a post on parenting or baby gear performance for this blog and running my little counselling office based out in Nairobi. Visit my Facebook profile here, and this is my LinkedIn profile, and here's my nascent youtube channel.

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