The right fit – a quick guide to car seat groups

When purchasing a car seat for your child you will encounter the following groups that help guide you to select the best seat for your child’s weight and age:


  • Group 0+: 0-13 kg (from birth to approx. 18 month)



  • Group 0+/I: 0-18 kg (combination seat, from birth to approx. 4 years)


  • Group I: 9-18 kg (approx. 9 months to 4 years)


  • Group I/II/III: 9-36 kg (combination seat – approx. 9 months to 12 years)


  • Group II/III: 15-36 kg (combination seat – approx. 3 to 12 years)



The choice of child restraint system depends on your child’s weight. Please ensure that the safety belt or harness fits well, since a badly fitting belt can cause serious injury.

From Group 0+ to Group I:

Babies should always be secured in a rearward-facing infant car for the first twelve months. There is no need to move your child to a Group I seat if their feet are poking out of the bottom or the child can sit up.

However, if the head protrudes above the edge of the seat and the baby weighs more than 13kg, you should change seats immediately, as the most vulnerable part of the child’s body is unprotected.

From Group I to Group II/III:

Should the child already be too heavy for its current seat and tall enough for a new seat, there is no reason why it should not move up a group. If the child’s head is above the top edge of the seat, we recommend you switch to Group II/III immediately. In this case, the child is often heavy enough to make the change anyway.

The following points apply in establishing whether the seat is the right size:

–          The seat is too small when more than a third of the child’s head rises above the seat’s top edge or the child’s harness in the top setting stretches over the child from an angle below the shoulders. Should this be the case, a car crash could cause serious, if not fatal injury.

–          It is equally important to ensure that the seat is neither too large nor too small. A seat is too large when the harness is far above the shoulders, even in the lowest setting.

Combination seats

Some child restraint systems span several groups, they have the ability to transform into a higher group, allowing them to grow with the child. The usual combinations are between Groups 0+ and I, and Groups I and II/III.

Group 0+/I seats are usually rearward-facing car seats. In this case, the child continues to face the rear, even after they have outgrown the infant carrier. This offers considerable safety benefits over forward-facing systems with integrated harnesses, as the child’s neck is not normally strong enough to support its head in an accident.

Group I/II/III combination seats have a life span of approx. 11 years. The material is especially designed for long-term use. Provided the owner observes the instructions, a high-quality seat should not suffer any wear and tear. Modern combination seats, such as the CYBEX Pallas 2-fix, offer the ISOFIX function in both groups, thus covering the whole period of use.

Read more at our Safety Centre.