According to the public health network, the largest jumpsuit on the market is only 90 yards, and children under 92 cm can wear it. In the final analysis, how big to wear is not a matter of time, but a matter of season. If the child is born in summer, it is enough to wear a jumpsuit until one year and eight months or one year and nine months. If the child is born in winter, it is best to wear it until he is over two years old.