Soft, safe and fully tested infant crib shoes designed to look like big kids soccer, baseball and football cleats. First Cleats complies with all applicable standards and rules set forth by the Consumer Product Safety Commission. The cleats from heel to toe measure 4.5". This measurement is equivalent to a size 2 infant shoe. Meant for pre-walking little kickers and not intended for actual sports. Babies feet vary greatly so how old they'll be when they can wear these will vary but typically it will be somewhere between 0 & 6 months.