The best car seat for your child fits your child correctly (by weight, height, and/or development), fits your car correctly, and you feel comfortable installing it safety every time.
Many car seats may overlap in terms of weight/height requirements, but a child may not be developmentally ready for certain seats.
For example, a 35 pound 3-year-old may "fit" into a booster with a 30 pound minimum weight, but that 3-year-old may not understand the idea of the seatbelt and try to “escape,” whereas if they were still seated in a car seat with a 5-point harness, it would be much more difficult for that child to get out of the seat.
Be sure to read the owner's manual for the car seat as well as for the vehicle; sometimes a car seat just won't fit in a vehicle.
A 5-point harness is found in most car seats, with two shoulder straps, two at the hips, and one crotch strap (note that some infant seats may have a 3-point harness).
A 3-point harness would also be found in a shoulder/lap seat belt, where you would have one strap at the shoulders, and two at the hips.
Children need to be rear-facing until age 2, or until they reach the maximum height and/or weight of their car seat.
When children max out their infant carrier car seat, they should use a rear-facing convertible car seat, which typically has a rear-facing maximum weight of 30-35 lbs.
Rear-facing seats have been found to be the most effective type of car seat. Placing a child in a forward-facing position before they are physically ready can result in serious injury or death. A rear-facing car seat does a better job of supporting the head, neck and spine of infants and toddlers in a crash, because it distributes the force of the collision over the entire body
Don't be concerned if your child's legs bend at the knees or touch the back seat of the car when rear facing. This will not harm his or her feet or knees.
The car seat should be tight enough that it doesn’t move more than an inch side-to-side or front-to-back right where the belt attaches to the car seat.
The harness straps should be snug enough that you cannot pinch any slack in the belt at the child’s shoulder.
Car seats should not be used longer than 6 years. Many car seats have an expiration date stamped into the plastic.
We do not recommend the use of secondhand car seats unless you know the history of the seat (meaning it has never been in a crash), it has not expired, and it has not been recalled.