Jo is a distinctive boys' name in United States, ranking #7174 in 1998 with 8 recorded births. This places Jo in the bottom 37% of ranked US boys' names for the year. Its actual usage is classified as Rare. The name reached its all-time peak in 2000 with 14 births ranking #5166. In 1998, approximately 1 in every 238,915 boys born was named Jo. FALLING Recent data shows the name is currently falling.