What is the child height and weight and age requirements for child car seats?

Child car seat requirements vary by state, but generally, children must use a car seat until they reach a specific height or weight limit, typically around 40-65 pounds and 4'9" tall. Infants should be in a rear-facing car seat until they are at least one year old and weigh at least 20 pounds, while toddlers can transition to a forward-facing seat with a harness once they outgrow the rear-facing seat. Booster seats are usually recommended for children aged 4 to 8 years until they can properly use a seatbelt. Always check local regulations for precise requirements.