Car Seat Guidelines – What You Need to Know

What you should know from AAP Car Seat Guidelines – car seat stages, types, ages, weight, and height limits.

A child safety seat is a must-have to ensure the littles’ safety in a car, from birth to the time when they’re ready for using a seat belt like an adult.

It’s not just because a car seat is required to ride a child by the US laws, but also your intention to protect your child by reducing the risk of injury or even death in a crash.

Because motor vehicle crashes are still the leading cause of death for children 4 years and older.

So you should follow the local laws to ride your little one in a car. Furthermore, it’s better to know the AAP car seat guidelines and NHTSA car seat tips.

General Car Seat Guideline from the AAP as of 2022

Infants and toddlers should be kept rear-facing as long as possible until they reach the highest weight or height allowed by their seats.

Updated guidance for families from AAP: Previously, there was a specific age milestone of 2 years old for rear-facing in the policy of 2011.

Later in 2018, AAP (American Academy of Pediatrics) updated its recommendations to keep a child in rear-facing as long as possible, up to the limits of their car seats.

America Academy of Pediatrics Guidance for Families

  • Children should ride in a rear-facing car safety seat as long as possible, up to the limits of their car safety seat. This will include virtually all children under 2 years of age and most children up to age 4.
  • Once they have been turned around, children should remain in a forward-facing car safety seat up to that seat’s weight and length limits. Most seats can accommodate children up to 60 pounds or more.
  • When they exceed these limits, child passengers should ride in a belt-positioning booster seat until they can use a seat belt that fits correctly.
  • Once they exceed the booster limits and are large enough to use the vehicle seat belt alone, they should always use a lap and shoulder belt.
  • All children younger than 13 years should be restrained in the rear seats of vehicles for optimal protection.

However, you still need to pay attention to your local city or state regulations anyway. Some US states require a toddler under 2 years old to stay rear-facing in the local law.

For example, the laws in California states that children under 2 years of age must be secured in a rear-facing car seat unless they weigh at least 40 lbs. or reach 40 inches in height. 

From the car seat guideline tips from AAP, you’ll find some clues that you’d better purchase the car seat based on your child’s ages and sizes like the weight and height, and the types, whether it’s rear- or forward-facing.

NHTSA has made many specific suggestions on the car seat types and stages based on your child’s age.

Choose a Car Seat Chart by Age

Car Seat Laws Age and Weight Charts

From the image of the car seat chart by age, you may have found that there are four stages – rear-facing, forward-facing, booster, and seat belt, that your child will go through from birth to youth.

In each stage, multiple types of car seats can be used to ride a child for safety. Based on the NHTSA’s method for classification, there are five or six types of car seats. We’ll follow its method to list all the car seat types in this guideline article later.

If you have tried to find a car seat, you may know that the manufacturers always indicate the car seat specs with the height and weight limits or range as a simple but direct tip to help pick up a perfect car seat for your child.

So, in this post, we’ll talk about these four topics – stage, age, type, and weight and height limits, with a few basic details that you need to know about car seats.

Car Seat Guideline by Stage

As your child grows, there will be four typical stages of using a car safety seat: Rear-facing car seats, forward-facing car seats, booster seats, and seat belts.

Each stage will last several years and there are various types of car seats suitable for children in the current stage.

Car Seat Stage 1: Rear-facing

Infants, especially small newborn babies, are safer to ride rear-facing. That’s why the AAP recommends that all infants ride rear-facing starting with their first ride home from the hospital. 

All infants and toddlers should ride in a rear-facing seat as long as possible until they reach the highest weight or height allowed by their car safety seat manufacturer.

More than the infant car seats for rear-facing use only, convertible and all-in-one car seats can be installed in rear-facing mode and they typically come with higher weight or height limits to let your child stay rear-facing for a longer time.

Infants below 12 months old should ride rear-facing. Some cities even require children under 2 years old in a rear-facing car seat for traveling.

Car Seat Stage 2: Forward-facing

You need to change your little one to forward-facing until they outgrow the height or weight limits of the rear-facing car seats. Now comes stage 2 to ride your child forward-facing.

It’s a common question that many parents ask: when can a baby face forward in a car seat?

The right or best answer for this question is to switch to front-facing as your infants approach the top weight or height of their car seats. Based on years’ experience, the height limit comes first.

Don’t rush to change the car seat to front-facing. Riding rear-facing is safer for your babies. So if you use a convertible or all-in-one car seat, it should allow your littles to stay until 2-3 years old.

But as long as your child exceeds the harness height or weight limits, which generally happens at 7-8 years old, you need to move to the next stage anyway.

Car Seat Stage 3: Booster

Your kid needs a booster after they outgrow the forward-facing car seats with a harness.

A booster seat is usually needed before your kid fits the seat belt properly like an adult. The least requirement to ride in a booster is that your child should be at least 4 years old.

Your child is ready for the next stage to use the vehicle’s seat belt when they outgrow the booster’s weight or height limits.

Car Seat Stage 4: Seat Belt

You’ll find that the fourth stage of using the vehicle’s seat belt starts from the eighth year, making it seems that your child is ready to use the seat belt at 8 years old

This is not the real case. Actually, big kids need at least a backless booster seat for riding until they’re 13 years old.

The American Academy of Pediatrics car seat guidelines also stated that children under 12 years old and not exceeding 57 inches tall should ride in a belt-positioning booster car seat for safety.

Car Seat Guideline - Types and Stages

The car seat types are related to the stages but not 100% the same. The NHTSA has been categorized into six types of car seats based on the functions. They are infant, convertible, all-in-one, combination, high back booster, and backless booster.

A few types of car seats will last for several stages, the convertible, all-in-one, and combination, for example; other car seat types can only last one stage, take the infant and booster for instance.

Only the first three stages need a car seat, the fourth stage doesn’t, but use the vehicle seat belt instead for stability and security. You can check which car seat fits your child in a specific stage as below.

Infant Car Seats - Stage 1

This type of car seat only supports rear-facing use and generally needs a base to install in the car. The infant car seats usually can be attached to a stroller from the same company to become a travel system for riding and strolling small babies and toddlers.

Infant car seats commonly come with a 30 or 35 pounds weight limit and 32 inches height limit, with a short-lasting from birth to 15-18 months.

Convertible Car Seats - Stage 1 and 2

Convertible car seats can be used both rear- and forward-facing. This type of car seat generally has higher weight and height limits in rear-facing mode and allows for fitting the littles longer in the first stage.

They commonly feature a 65-pounds top weight limit and 49-inches tall for big kids and ride them until 7-8 years old before outgrowing the harness weight or height limits.

All-in-one Car Seats (3-in-1 and 4-in-1) - Stage 1, 2 and 3

All-in-one car seats, based on the NHTSA’s suggestion, can change from a rear-facing seat to a forward-facing seat (with a harness and tether) and to a booster seat as a child grows. 

That means, this type of car seat, including 3-in-1 or 4-in-1, is designed to go through the first three stages from day one to the day when your child is ready to use the seat belt for security.

Combination Car Seats - Stage 2 and 3

This type of car seat combines two features with a seamless transition from a forward-facing seat with a harness and tether into a booster. Sometimes they are called harness boosters in the name. 

The combination car seats can be used forward-facing only for big toddlers. A few advanced models may combine three features: harness, high back booster, and no-back booster.

Booster Seat with High Back - Stage 3

This type of booster seat is designed to boost the child’s height so the seat belt fits properly. It also provides neck and head support and is ideal for vehicles that don’t have head rests or high seat backs.

Backless Booster Seat - Stage 3

A backless booster seat is designed to boost the child’s height so the seat belt fits properly. It does not provide head and neck support. It is ideal for vehicles that have headrests.

Car Seat Guideline by Age

Age is a very common but simple factor to choose a perfect child safety seat. You’ll find age appears often in the car seat laws of each state. So it’s recommended to read the local laws that provide a few tips on which age needs which type of car seat before purchasing a car seat.

There are several typical ages to decide the car seat stage and types, and position of rear-facing or forward-facing or not: 2 years, 4 years, and 8 years.

2 Years Old - Car Seat Position

Can I turn my 2 year old forward facing? 

This is a very common and classic question that parents ask most often and don’t know how to accommodate the littles at this age –  rear-facing or front-facing. 

Some US states require that toddlers below 2 years old should ride rear-facing, like California, New Jersey, Illinois, etc.

If you’re living or planning to travel in these states, it’s better to ride your child in a car seat that allows 2 years old toddlers to stay rear-facing.

Plus, the AAP also suggests keeping the infants rear-facing as long as possible. 

So even if you’re living in other states that don’t ask the 2 years old child to face rear in their car seat,  it’s better to insisting fitting them rear-facing on the second birthday unless they exceed the height or weight limits that the car seat’s manufacturers allow.

4 Years Old - Car Seat Type

Are booster seats safe for 4 year olds?

When your toddler grows to 4, you may have this question in your mind and want to change to a booster for them.

Not take action so quickly if you have one kid and have purchased a convertible or all-in-one car seat going through the second forward-facing (or 5-point) stage. 

4 years old is the minimum age requirement for a child to move into a booster seat. The best way to ensure your child’s safety is to delay the transition as long as possible.

4-year old or bigger children can fit well with a harness and tether for riding safely and they should be protected with a 5-point harness until they outgrow the height or weight limits.

8 Years Old - Car Seat or No?

Does an 8 year old need a car seat?

This question appears in the parents’ minds when their kids grow to this age or even earlier at 6 or 7 years old. 

The best guide is to check your local laws, while most states require an 8-year-old child to stay in a car seat. 

The following are the NHTSA’s tips, which also recommend keeping a child 8 years old or younger in a child safety seat as long as possible until they outgrow their car seat.

Big kids of 8 years old outgrow their car seats can wear the vehicle’s seat belt for safety, just as an adult. However, for your child’s safety, a booster, or at least a backless booster, is a good choice for safer riding in automobiles.

Car Seat Guidelines Height and Weight

The height and weight limits are the leading factors for choosing the best car seat for a child. It’s better and safer to ride a child in a car seat within its weight and height limits in the current stage.

Each car seat has its own minimum and maximum limits so check your car seat’s instruction manual before using the seat.

Typical Minimum Requirements:


The height and weight limits are the leading factors for choosing the best car seat for a child. It’s better and safer to ride a child in a car seat within its weight and height limits in the current stage.

Each car seat has its own minimum and maximum limits so check your car seat’s instruction manual before using the seat.


Height: Toddlers with a minimum height range between 28-24 inches tall, depending on the models and car seat types.

Weight: Toddlers with a minimum weight of 20-25 lbs.


Height: Children with a minimum height range between 38-44 inches tall.

Weight: Children with a minimum weight of 40 pounds.

Seat belt

Height: Big kids with a minimum height of 49-inches tall.

Age: 8 years old or more.

Typical Maximum Limits:


Weight: Infants with a maximum weight of 30 to 35 lbs.

Height: Infants with a maximum height of 32 inches for most rear-facing only infant car seats, and 40-43 inches for convertible car seats used in rear-facing.


Height: Toddlers at most 49-inches tall for most convertible car seats used in forward-facing, some special cases include 52-inch for Maxi-Cosi Pria 85 Max, and 54-inches for Chicco Fits4 4-in-1 car seat.

Weight: Toddlers with a maximum weight of 65 lbs and 85 lbs (only for Maxi-Cosi Pria 85 Max).


Height: Children with a maximum height range between 52 inches and 63 inches tall.

Weight: Children with a maximum weight of 100-120 pounds.

Seat belt

Age: 8 years old or more

Basic Car Seat Glossary You Should Know

The car seat is not that easy to understand for first-time parents who look for a perfect car seat for their first baby.

That’s why we wrote this quick guide that lists and explains some of the most common car seat terms you will see in the seats’ product descriptions and user manual. 

We hope this guide will help you better understand the car seat safety systems, accessories, and other terms so that you can find the best car seat for your baby.

Adjustable Foot: It’s a part of the detachable base and is mainly used to adjust a rear-facing car seat for up and down to make sure the seat is installed at the right angle, generally found in infant, convertible, or all-in-one car seats.

Aftermarket products: These are the replacement parts or products sold for a used car seat or one that has been broken. Avoid using these products and think twice even if they are made or allowed by original car seat manufacturers.

Automatic locking retractor: This is used to lock the seat belt at a set position so that it keeps the seat belt tight enough around your baby. 

It’s an important piece when installing car seats because it will lock to hold the baby in place during a crash. 

This part is generally found in the car, so you can check the vehicle owner’s manual for more details.

Belt-positioning booster seat: It’s a traditional booster seat to boost your child up, that uses the built-in belt to guide to position the vehicle seat on your child. 

This type of seat provides a higher sitting height, which allows the adult lap and shoulder belt to fit properly. But now it’s categorized as a booster car seat.

Belt Path: This is the path on a car seat or booster seat where a seat belt or lower anchor attachment is placed to secure the car seat in the vehicle. Forward- and rear-facing will often have separate belt paths. Generally, the rear-facing belt path is at a lower position than the forward-facing belt path. Be sure to use the correct one.

Buckle: This is used to connect and lock the harness system.

Car Bed: A restraint used for newborn babies who are too small for a traditional infant car seat or have a special medical need that should ride lying flat. 

There will also be an internal harness that can secure the baby in the car bed. Check the manufacturer’s instructions and car seat manuals if needed to secure specific car beds.

Chest Clip: This is the plastic buckle or clasp that holds the harness shoulder straps together over the child’s chest. It’s properly positioned at the armpit level.

Carry handle: Generally found in an infant car seat. It’s a plastic handle attached to the car seats and can be used to carry a car seat without disturbing the child in it when removed from a vehicle.

Detachable base: This is a separate base for a rear-facing only car seat that can be installed in the vehicle to secure the car seat. The car seat part can be removed from the base and used as a carrier. 

To make it more convenient for you to switch between several vehicles, there are separate bases available for sale, saving you money to buy several infant car seats.

Emergency locking retractor: This is a retractor to lock the seat belt for safety when the vehicle slows or stops suddenly.

Harness: It’s the straps that keep the child in the car seat and spreads out crash forces. All car seats are required to be equipped with harness straps which are fed through harness slots.

Right now, there are two harness types that meet FMVSS 213 requirements:

5-Point: Harness has five points of contact with one over each shoulder,

one on each side of the pelvis, and one between the legs; All the five points are coming together at a common buckle named harness buckle.

3-Point: Two less than the 5-points, only has three points of contact that includes two shoulder straps coming together at one buckle in the shell or on a crotch strap. NOT to be confused with a 3-point (lap-and-shoulder) vehicle belt.

Harness buckle: This is a place where the harness system connects and locks, to secure the straps that contact the child’s shoulders, hips, and groin.

Harness adjuster: This is the part that is used to adjust the harness straps of a car seat for comfortable tightness.

Harness slots: These are the parts on a car seat that the harness straps go over the seat shell.

Labels: These are the information required by Federal standards affixed to car seats or booster seats. They are often found on the side of the car seats, including some warnings and notices for parents to use the car seats.

Level indicator: This is a part of the car seat used to help identify if you have installed the car seat in right rear-facing recline angles or not. Make sure to pay special attention to the recline angle, which is very important for newborn babies who can’t hold their heads up.

Locking clip: This device will help to hold a car seat in the proper position during normal driving if there is no other locking mechanism available.

Lower anchors: These are the horizontal bars in the vehicle seat that will provide a secure anchor for the car seat’s lower attachments.

Lower anchor attachments: They are the attachments on a car seat and can be used to secure a car seat or booster seat by connecting to the lower anchors embedded in the vehicle backseat. As your child grows over 65 pounds, you can switch to use the vehicle belt for installation.

Recalls: The car seat manufacturers work together with the NHTSA to repair any defects after the products have been distributed or sold. All repairs or replacements for products recalled for violations of safety standards must be free. 

So check regularly if your car seat is on the list of recalls or not, and take positive actions to get free repairs or replacement if yes.

Recline adjuster: This is a device to adjust the angle of the car seat to ensure the child stays in the proper position no matter in the rear-facing or forward-facing mode.

Registration card: It’s a card that comes with every car seat and should be returned to the manufacturer so that you can be notified promptly if there are any recalls.

Retractor: It’s a mechanism that works with the seat belts to gather and store extra seat belt webbing.

Seat Belt Syndrome: It is a collective term that includes all injury profiles such as bruising, internal injuries, or fractures that might occur in a crash or sudden braking when the seat belts do their job. To avoid these injuries, children should be buckled in with a lap and shoulder belt, to provide upper body protection.

Shell: This is a molded plastic and/or metal structure of a car seat or booster seat. Also called a frame in some car seats.

Smart AirBag System: It’s a smart airbag system that uses a sensor to detect the weight and seating position of any passenger in the vehicle. It also notes whether or not the seat belt is fastened. 

When the car is in a crash, the smart airbag system will deploy to protect the passenger and make a decision as to how hard the airbag will shoot off its compartment. Smaller passengers like children will get a gentler airbag deployment for safety. 

NOTE that not all cars have this system.

Switchable retractor: This is a retractor that can be switched from an emergency locking retractor to an automatic locking retractor for use when installing car seats.

Tether: It includes a tether strap and tether hook that anchors the top of a forward-facing car seat to the tether anchor in the vehicle. The tether helps to keep restraint from tipping forward on impact and can provide extra protection against head injuries. 

You’ll find it is located on the top rear of all car seats when used forward-facing. Generally, the rear-facing-only infant car seats do not use this equipment for installation.

Tether anchor: It’s a device that can be used to connect the tether at a designated anchor point in the vehicle.

Safety Tips to Keep in Mind

The wrong car seat and booster seat installations are the major causes for kids’ death in a car crash, while the rates of car seat, booster seat, and seat belt misuse vary from 74 to 90 percent. 

To ensure your kid’s safety in your car, you not just need to pick up the right car seat, but also make sure you have installed the car seat in your car correctly.

Here are some tips for you to know for a car safety seat installation and use:

  • Purchase a car seat that is appropriate for your child’s height and weight.
  • NOT buy any used car seats.
  • Use the lowest harness slots for a newborn infant, make sure the straps in the slots at or below your baby’s shoulders for the rear-facing position.
  • Keep your baby to ride sitting semi-reclined for safety and comfort, about halfway back or 45 degrees from horizontal.
  • Never use any car seat or booster car seat in a seat with an airbag.
  • Register the card and send it to the manufacturer in case your car seat is recalled.
  • Make sure the car seat is installed tightly enough. The seat shouldn’t move more than 1-inch side to side or front to back once installed.
  • Make sure you have installed your car seat correctly. We have some installation tips.
  • Follow manufacturer’s instructions for installation. If you have any questions, contact the manufacturer.