Which car seat for which height?
From infant carrier to toddler seat to high-back booster: which seat fits which height, when to move on and what the law says.
40–87 cm: the infant carrier
The first car seat is usually an infant carrier: a portable shell that faces backwards in the car. Most are approved from 40 or 45 cm up to about 75 to 87 cm. Manufacturers describe that roughly as birth to about 12 to 15 months.
Many infant carriers click onto an Isofix base that stays in the car and, with adapters, onto a pram chassis. Handy for short trips, but follow the manual on how long your baby may lie in it at a stretch.
76–105 cm: the toddler seat
Next comes a seat for about 76 to 105 cm, roughly from 15 months to 4 years. Many of these seats can face backwards or forwards; some are rear-facing only.
Under the i-Size regulation (UN R129), your child travels rear-facing until at least 15 months. An i-Size seat may face forwards only from 76 cm and 15 months; many seats stay rear-facing up to 105 cm.
100–150 cm: the high-back booster
From about 100 cm, around 3.5 to 4 years, your child moves to a high-back booster. The child is then held by the car’s own three-point belt; the booster makes the belt run properly over the shoulder and hips.
Under the new rules, a booster cushion without a back is only approved for children from 125 cm. Many high-back boosters last up to 150 cm.
Seats that grow along
Some seats cover several classes, such as 40–105 cm, 61–105 cm or 76–150 cm. That saves a purchase, but such a seat is bigger and heavier and usually can’t be carried. On LeBaby, a multi-class seat appears in every class it covers.
When do you move on?
The height and weight on the label and in the manual decide. For infant carriers, manufacturers often mention the head too: once it sticks out above the rim of the shell, it’s time for the next seat. Check what your own manual says.
Feet touching the car seat’s backrest or bent legs are, according to many manufacturers, no reason to move on early or to turn forwards.
What does the law say?
In the Netherlands and Belgium, a child shorter than 1.35 metres must travel in an approved child seat that fits their height or weight. A rear-facing seat may not go on the front passenger seat if the airbag there is active: it must be switched off.
Common questions
Until what age should my child face backwards?
Under the i-Size regulation (UN R129), until at least 15 months. An i-Size seat may face forwards only from 76 cm and 15 months. Many seats can stay rear-facing longer; the manual says up to which height and weight.
How long does my baby fit in the infant carrier?
Up to the maximum height or weight the manufacturer states, often between 75 and 87 cm. If the manual says the head must not stick out above the shell, that applies too.
From what height may a child travel without a car seat?
In the Netherlands and Belgium, from 1.35 metres. Below that, your child must be in an approved child seat that fits their height or weight.
Keep looking
LeBaby doesn’t test products. This guide sets out what the standards and manufacturers say. Always follow the manual of your own product.
More guides
- How to choose a pram Travel system, 3-in-1 or straight to a pushchair? What to look for in the type, the lying position, the fold and your own daily routes. Read the guide
- i-Size explained What the car-seat standard i-Size (UN R129) means, how the height classes work and why your baby rides rear-facing for longer. Read the guide
- Crib, bedside crib or cot? The difference between a crib, a bedside crib and a cot, which sizes are common and when your baby outgrows them according to the manufacturer. Read the guide
