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Children are safest in the right seat for their size: rear-facing for as long as possible, then a forward-facing seat with a 5-point harness, then a high-back booster until the adult belt fits (about 135–150 cm).
Enter your child's age, height and weight to see the right stage and the rules where you live — UK law requires a seat until 12 years or 135 cm, US guidance is to use a booster until 145 cm, and India has rules for children on two-wheelers.
| Age | 30 months |
| Child's Height | 92 |
| Length Unit | cm |
| Child's Weight | 13 |
| Weight Unit | kg |
| Country | UK / Europe |
| Recommended car seat | Rear- or forward-facing seat with a 5-point harness |
| Why | Use the harness until the child reaches the seat's maximum height or weight |
| Seat position | Back seat — never in front of an active airbag if rear-facing |
| Law and guidance | UK law: a car seat is required until 12 years or 135 cm (whichever first). i-Size (R129) seats: rear-facing until at least 15 months; boosters (cushions) only for children over 125 cm and 22 kg. |
Rear- or forward-facing seat with a 5-point harness.
Try this example →| Age | 84 months |
| Child's Height | 122 |
| Length Unit | cm |
| Child's Weight | 23 |
| Weight Unit | kg |
| Country | India |
| Recommended car seat | High-back booster seat with the adult seat belt |
| Why | Until at least 135 cm, ideally 145–150 cm, when the adult belt fits |
| Seat position | Back seat — never in front of an active airbag if rear-facing |
| Law and guidance | India: no national car-seat law is in force yet for cars, but the Motor Vehicles Act 2019 provides for child restraints under 14; on two-wheelers, children 9 months–4 years must wear a crash helmet and safety harness, and speed is limited to 40 km/h. A rear-facing or harnessed seat is strongly advised (look for ECE R44/R129 labels). |
High-back booster seat with the adult seat belt.
Try this example →At least 15 months (UK i-Size law), and ideally until 2–4 years or the seat's limit.
After outgrowing a harnessed seat, usually 4 years and 18 kg or more; UK backless cushions only for over 125 cm and 22 kg.
Ideally not before 13 years; never in a rear-facing seat in front of an active airbag.
Not yet enforced for cars nationally, but strongly recommended; children aged 9 months to 4 years on two-wheelers must wear a helmet and harness.