Car Seat Timelines: A Background on Car Seats for Your Baby

As a parent or parent-to- be, are you overwhelmed by the whole idea of car seats? I was in the same spot. What are all the different kinds of car seats? This handy car seat timeline will help you understand the ins and outs of car seats! And as an added nerdy bonus, I’ve rounded up some other fun car seat infographics you’ll enjoy! 

Why are there so many different kinds of car seats? 

To put it simply, your car is designed for keeping adults safe. Airbags are dangerous to small children, and regular seat belts don’t fit them right. So car seats provide the right protection for your child until they are big enough to fit in a regular seat. 

How important are car seats? 

The CDC explains just how important car seats are:

In the United States, motor vehicle crashes are a leading cause of death among children…
In 2017, restraint use saved the lives of 325 children ages 4 years and younger. Car seat use reduces the risk for injury in crashes by 71–82% for children, when compared with seat belt use alone.

Booster seat use reduces the risk for serious injury by 45% for children aged 4-8, when compared with seat belt use alone

CDC, Child Passenger Safety Information

Rear- facing is safest

Children should be transported in a rear-facing child seat for as long as possible. Why? It’s the safest orientation for injury avoidance in a crash.  The usual cause of injury to a child in a crash is contact with the interior of the vehicle, and the child seat restrains them from this. In rear-facing seats, the child is pressed against the child seat with its back, neck, and skull completely supported by the child seat’s padded, impact-absorbing material.  In the front-facing position, these same forces are applied to the child’s chest and torso where the straps secure it, and the more concentrated force has a higher chance of causing injury. Overwhelmingly, organizations like the American Academy of Pediatrics, the National Institute of Highway Safety, and the Children’s Hospital of Philadelphia recommend transporting children in a rear-facing child seat until reaching the maximum height and weight for that seat. That’s 2 years of rear-facing at a minimum, with 4 years rear-facing being even better!
Alright, now that we’re done with the serious statistics, let’s talk about car seats. 

What are the different types of car seats? 

Wait, one more bit of administrative stuff first. All car seats are required to pass certain safety tests. So any car seat is good, even if it is low cost or doesn’t have all the bells and whistles. Some car seats with added features are even better.  OK, now let’s get to the point.

An infant seat looks kind of like a bassinet. It’s a rear- facing seat for kids under 2. They often come with bases so you can easily use the car seat in multiple vehicles. 

Example of an infant seat: the Graco SnugRide SnugLock 35

Next up is the convertible car seat. The convertible car seat is rear facing, but converts (ha! See what I did there?) to face forward when the child is ready, between 2-4 years old. 

Example of a convertible car seat: the Combi Coccoro can face rearward or forward

Some parents want to play it safe and keep their child rear-facing for longer. Then an extended rear-facing seat is what you’re looking for! These seats are designed to hold larger kids so they can rear-face for longer.

Example of an extended rear-facing car seat: the Graco Extend2Fit. Note the light gray thingy under the kid’s feet that give him more room!

And once your child is big enough, they’re ready for a booster seat. There are a few different kinds- some have backs and others are backless booster seats. These seats prop your kids back and butt up so seat belts fit them properly.

Example of a belt-positioning booster seat: the Britax Midpoint

Example of a backless booster seat: the Cosco Topside. Unlike the backless booster, it’s basically a cushion that raises the child so the seat belt fits properly.

Some parents don’t want to buy so many different car seats. So there’s the option of 3-in-1 car seats. They can go from rear-facing to forward facing to booster seats, depending on the child’s age. Or to put it another way, they’re basically a convertible car seat that also converts into a booster seat. The downside of these seats is that they are jacks of all trades and masters of none. That is to say, they do a decent job at all of those sizes, but they may not fit as well as a seat specifically designed for an infant, toddler, and child.

Finally, for the parents who really want it all, there’s the 4-in-1 car seat. These seats transition from rear-facing to forward facing, to booster seats with backs, to booster seats without backs. Or, they’re a 3-in-1 seat that also transitions to a backless booster.

Car Seat Timeline: A General Guide of What Seat to Use When

I have to preface this section with the fact that every child and every car seat is different. Be sure to read your car seat’s owners manual to understand the specifics of your seat. As you’ll see, depending on your child’s height and weight, they may outgrow their car seat sooner or later than the average age.

car seat timeline infographic

Infant seats are rear-facing only, and hold children around from 4-35 pounds, and up to 32 inches in height depending on the brand. The average child will outgrow their seat height-wise first. For example, the average child will reach 35 pounds around age 4, but will be 32 inches tall by 18 months.[Source: CDC growth charts]. 

Rear-facing convertible car seats, on average, hold children from 5-40 pounds and 19-40 inches tall. Weight-wise, this is around birth to age five. Height-wise, that’s about birth to age four. Any rear-facing seat will cradle and protect your child’s fragile neck and spinal cord in the event of a crash. This is why it’s important for children to remain rear facing until at least 2 years. But rear-facing for longer is safer! [sources: CDC, NHTSA, American Academy of Pediatrics]

Forward-facing convertible car seats, on average, hold children from 20-40 pounds and 28-50 inches.  The average child may reach 20 pounds and 28 inches around 9 months, but they definitely shouldn’t face forward that early! Most organizations recommend age 2 as the minimum for forward facing, and age 4 is preferred! They’ll reach 40 pounds around age 5. As for height, they’ll hit 50 inches around age 8! For forward facing seats, you can see kids outgrow them by weight first. The five-point harness and tether of a forward-facing seat limit your child’s forward momentum during a crash much better than a seat belt. 

Anyways, once they outgrow the forward-facing seat, then they are ready for…

Booster seats! Booster seats come in several types, since children may be big enough for them any time between age 4 and 7! They always consist of a butt cushion to raise your child up off the seat, so that the seat belt sits properly across their lap and shoulders. They may or may not have a back. Booster seats are recommended until a child is big enough to properly wear a seat belt. This is typically somewhere between the ages of 9 and 12. A child is ready for a seat belt when they meet all five criteria below:

  1. The child can sit with their back against the vehicle’s seat.
  2. The child’s knees bend at the edge of the seat.
  3. The lap belt lays across their upper thighs and not the stomach. 
  4. The shoulder belt should lay across the chest and not the neck.
  5. The child can sit properly without slouching or leaning over

Other Car Seat Timelines

As you might have guessed, I’m a nerd, which means I like graphs and charts. So here are some of my favorite car seat timelines from other sources.

The CDC’s car seat timeline has nice, detailed pictures and explanations.

cdc car seat timeline

Consumer Reports has a simple and clean timeline

Consumer Report's car seat timeline

I like this one from TheCarSeatLady.com! 

Conclusions: Car Seat Timelines

Thank you for reading! I hope you learned something or at least had fun looking at all the car seat timelines, graphs and charts!

Looking for more information about car seats? Check out these articles:

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