To be sure you are getting the right size, measure from the child’s collar to where you want the tie to end. Then pick the closest size to your measurement.
Approximate sizes are:
Infant: 0-6 months
Toddler: 6 months -3T
Boy: 4T-Child size 6
Youth: Child size 7-9
It should be noted that when ties are on infants and toddlers they need constant adult supervision.